Nitrosated and nitrosylated potassium channel activators, compositions and methods of use

ABSTRACT

The present invention describes novel nitrosated and/or nitrosylated potassium channel activators, and novel compositions comprising at least one nitrosated and/or nitrosylated potassium channel activator, and, optionally, at least one compound that donates, transfers or releases nitric oxide, elevates endogenous levels of endothelium-derived relaxing factor, stimulates endogenous synthesis of nitric oxide or is a substrate for nitric oxide synthase and/or at least one vasoactive agent. The present invention also provides novel compositions comprising at least one potassium channel activator, and at least one compound that donates, transfers or releases nitric oxide, elevates endogenous levels of endothelium-derived relaxing factor, stimulates endogenous synthesis of nitric oxide or is a substrate for nitric oxide synthase and/or at least one vasoactive agent. The present invention also provides methods for treating or preventing sexual dysfunctions in males and females, for enhancing sexual responses in males and females, and for treating or preventing cardiovascular disorders, cerebrovascular disorders, hypertension, asthma, baldness, urinary incontinence, epilepsy, sleep disorders, gastrointestinal disorders, migraines, irritable bowel syndrome and sensitive skin.

RELATED APPLICATIONS

This application claims priority to U.S. Provisional Application No.60/133,888 filed May 12, 1999.

FIELD OF THE INVENTION

The present invention describes novel nitrosated and/or nitrosylatedpotassium channel activators, and novel compositions comprising at leastone nitrosated and/or nitrosylated potassium channel activator, and,optionally, at least one compound that donates, transfers or releasesnitric oxide, elevates endogenous levels of endothelium-derived relaxingfactor, stimulates endogenous synthesis of nitric oxide or is asubstrate for nitric oxide synthase and/or at least one vasoactiveagent. The present invention also provides novel compositions comprisingat least one potassium channel activator, and at least one compound thatdonates, transfers or releases nitric oxide, elevates endogenous levelsof endothelium-derived relaxing factor, stimulates endogenous synthesisof nitric oxide or is a substrate for nitric oxide synthase and/or atleast one vasoactive agent. The present invention also provides methodsfor treating or preventing sexual dysfunctions in males and females, forenhancing sexual responses in males and females, and for treating orpreventing cardiovascular disorders, cerebrovascular disorders,hypertension, asthma, baldness, urinary incontinence, epilepsy, sleepdisorders, gastrointestinal disorders, migraines, irritable bowelsyndrome, and sensitive skin.

BACKGROUND OF THE INVENTION

Adequate sexual function is a complex interaction of hormonal events andpsychosocial relationships. There are four stages to sexual response asdescribed in the International Journal of Gynecology & Obstetrics,51(3):265-277 (1995). The first stage of sexual response is desire. Thesecond stage of sexual response is arousal. Both physical and emotionalstimulation may lead to breast and genital vasodilation and clitoralengorgement (vasocongestion). In the female, dilation and engorgement ofthe blood vessels in the labia and tissue surrounding the vagina producethe “orgasmic platform,” an area at the distal third of the vagina whereblood becomes sequestered. Localized perivaginal swelling and vaginallubrication make up the changes in this stage of sexual response.Subsequently, ballooning of the proximal portion of the vagina andelevation of the uterus occurs. In the male, vasodilation of thecavernosal arteries and closure of the venous channels that drain thepenis produce an erection. The third stage of sexual response is orgasm,while the fourth stage is resolution. Interruption or absence of any ofthe stages of the sexual response cycle can result in sexualdysfunction. One study found that 35% of males and 42% of femalesreported some form of sexual dysfunction. Read et al, J. Public HealthMed., 19(4):387-391 (1997).

While there are obvious differences in the sexual response between malesand females, one common aspect of the sexual response is the erectileresponse. The erectile response in both males and females is the resultof engorgement of the erectile tissues of the genitalia with blood whichis caused by the relaxation of smooth muscles in the arteries servingthe genitalia.

In males, some pharmacological methods of treating sexual dysfunctionsare available, however, such methods have not proven to be highlysatisfactory or without potentially severe side-effects. Papaverine isnow widely used to treat impotence. Papaverine is generally effective incases where the dysfunction is psychogenic or neurogenic and wheresevere atherosclerosis is not involved. Injection of papaverine, asmooth muscle relaxant, or phenoxybenzamine, a non-specific antagonistand hypotensive, into corpus cavernosum has been found to cause anerection sufficient for vaginal penetration, however, these treatmentsare not without the serious and often painful side effect of priapism.Also, in cases where severe atherosclerosis is not a cause of thedysfunction, intracavernosal injection of phentolamine, an α-adrenergicantagonist, is used. As an alternative or, in some cases, as an adjunctto α-adrenergic blockade, prostaglandin E₁ (PGE₁) has been administeredvia intracavernosal injection. A major side effect frequently associatedwith intracorprally delivered PGE₁ is penile pain and burning.

Potassium channel activators have been developed to treat numerousdiseases. For example, Gopalakrishnan et al, Drug Dev. Res. 28:95-127(1993) describe this class of compounds for treating diseases such ashypertension, asthma, hair growth, ischemia and urinary incontinence;U.S. Pat. Nos. 5,256,688 and 5,354,764 disclose the use of pinacidil orcromakalim for treating myocardial ischemia; U.S. Pat. No. 5,262,419discloses treating ulcerative gastrointestinal conditions; U.S. Pat. No.4,792,564 discloses treating and preventing cerebral vasospasms; U.S.Pat. No. 4,789,679 discloses treating incontinence; U.S. Pat. No.4,057,636 discloses the use of potassium channel activators for loweringblood pressure; U.S. Pat. No. 5,869,509 discloses the use of potassiumchannel activators for treating ischemia, convulsions, asthma, irritablebowel syndrome, migraine, traumatic brain injury, male erectiledysfunction and urinary incontinence; WO 99/11238 discloses the use ofpotassium channel activators for treating sensitive skin, particularlyfor the elimination of itching, pruritus, stabbing pains, tinglingand/or erythema; Aizawa et al, J. Cardiovasc. Pharmcol. 10:S123-S129(1987) describes the use of nicorandil for treating ischemic heartdisease; U.S. Pat. No. 4,617,311 discloses the use of potassium channelactivators for treating asthma; and Boselli et al, Clin. Neuropharmacol20(3):252-263 (1997) compares the use of lorazepam with other compoundsas sedatives for treating insomnia. The disclosure of each of thesepatents, applications and publications is incorporated by referenceherein in their entirety.

There is a need in the art for new and improved treatments of male andfemale sexual dysfunctions and other diseases, particularly treatmentsthat do not have the undesirable side effects of those agents currentlyused. The present invention is directed to these, as well as other,important ends.

SUMMARY OF THE INVENTION

Nitric oxide (NO) has been shown to mediate a number of actions,including the bactericidal and tumoricidal actions of macrophages andblood vessel relaxation of endothelial cells. NO and NO donors have alsobeen implicated as mediators of nonvascular smooth muscle relaxation. Asdescribed herein, this effect includes the dilation of the corpuscavernous smooth muscle, an event involved in the sexual responseprocess in both males and females. However, the effects of modifiedpotassium channel activators, which are directly or indirectly linkedwith a nitric oxide adduct, and which are optionally used in conjunctionwith NO donors, have not been previously investigated.

In arriving at the present invention, it was unexpectedly discoveredthat the adverse effects associated with potassium channel activatorscan be avoided by the use of nitrosated and/or nitrosylated potassiumchannel activators or by the use of at least one potassium channelactivator in combination with at least one nitric oxide donor. Suchadverse effects include postural hypotension, headaches, dizziness,palpitations, gastric pain, nausea and vomiting. The smooth musclerelaxant properties of the potassium channel activators and of compoundsthat donate, release or transfer nitrogen monoxide or elevate levels ofendogenous nitric oxide or endothelium-derived relaxing factor (EDRF) orare substrates for nitric oxide synthase work together to permit thesame efficacy with lower doses of the potassium channel activators orwork synergistically to produce an effect that is greater than theadditive effects of the potassium channel activators and the compoundsthat donate, release or transfer nitrogen monoxide or elevate levels ofendogenous nitric oxide or EDRF or is a substrates for nitric oxidesynthase.

One aspect of the present invention provides novel nitrosated and/ornitrosylated potassium channel activators. The potassium channelactivators can be nitrosated and/or nitrosylated through one or moresites such as oxygen (hydroxyl condensation), sulfur (sulfhydrylcondensation), carbon and/or nitrogen. The present invention alsoprovides compositions comprising a therapeutically effective amount ofsuch compounds in a pharmaceutically acceptable carrier.

Another aspect of the present invention provides compositions comprisinga therapeutically effective amount of at least one potassium channelactivator, that is optionally substituted with at least one NO and/orNO₂ group (i.e., nitrosylated and/or nitrosated), and at least onecompound that donates, transfers or releases nitrogen monoxide as acharged species, i.e., nitrosonium (NO⁺) or nitroxyl (NO−), or as theneutral species, nitric oxide (NO.), and/or stimulates endogenousproduction of nitric oxide or EDRF in vivo and/or is a substrate fornitric oxide synthase. The present invention also provides for suchcompositions in a pharmaceutically acceptable carrier.

Yet another aspect of the present invention provides compositionscomprising a therapeutically effective amount of at least one potassiumchannel activator, that is optionally substituted with at least one NOand/or NO₂ group (i.e., nitrosylated and/or nitrosated), at least onevasoactive drug, and, optionally, at least one compound that donates,transfers or releases nitrogen monoxide as a charged species, i.e.,nitrosonium (NO⁺) or nitroxyl (NO−), or as the neutral species, nitricoxide (NO.), and/or stimulates endogenous production of nitric oxide orEDRF in vivo and/or is a substrate for nitric oxide synthase. Theinvention also provides for such compositions in a pharmaceuticallyacceptable carrier.

Yet another aspect of the present invention provides methods fortreating and/or preventing sexual dysfunctions and/or enhancing sexualresponses in patients, including males and females, by administering toa patient in need thereof a therapeutically effective amount of at leastone nitrosated and/or nitrosylated potassium channel activator and,optionally, at least one compound that donates, transfers or releasesnitric oxide as a charged species, i.e., nitrosonium (NO⁺) or nitroxyl(NO−), or as the neutral species, nitric oxide (NO.), and/or stimulatesendogenous production of nitric oxide or EDRF in vivo and/or is asubstrate for nitric oxide synthase. The methods can further compriseadministering a therapeutically effective amount of at least onevasoactive agent. Alternatively, the methods for treating and/orpreventing sexual dysfunctions and/or enhancing sexual responses inpatients, including males and females, can comprise administering atherapeutically effective amount of at least one nitrosated and/ornitrosylated potassium channel activator, at least one vasoactive agent,and, optionally, at least one compound that donates, transfers orreleases nitric oxide as a charged species, i.e., nitrosonium (NO⁺) ornitroxyl (NO−), or as the neutral species, nitric oxide (NO.), and/orstimulates endogenous production of nitric oxide or EDRF in vivo and/oris a substrate for nitric oxide synthase. The nitrosated and/ornitrosylated potassium channel activators, nitric oxide donors, and/orvasoactive agents can be administered separately or as components of thesame composition in one or more pharmaceutically acceptable carriers.

The present invention also provides methods for treating and/orpreventing sexual dysfunctions and/or enhancing sexual responses inpatients, including males and females, by administering to a patient inneed thereof a therapeutically effective amount of at least onepotassium channel activator and at least one compound that donates,transfers or releases nitric oxide as a charged species, i.e.,nitrosonium (NO⁺) or nitroxyl (NO−), or as the neutral species, nitricoxide (NO.), and/or stimulates endogenous production of nitric oxide orEDRF in vivo and/or is a substrate for nitric oxide synthase. Themethods can further comprise administering a therapeutically effectiveamount of at least one vasoactive agent. Alternatively, the methods fortreating and/or preventing sexual dysfunctions and/or enhancing sexualresponses in patients, including males and females, can compriseadministering a therapeutically effective amount of at least onepotassium channel activator, at least one vasoactive agent, and,optionally, at least one compound that donates, transfers or releasesnitric oxide as a charged species, i.e., nitrosonium (NO⁺) or nitroxyl(NO−), or as the neutral species, nitric oxide (NO.), and/or stimulatesendogenous production of nitric oxide or EDRF in vivo and/or is asubstrate for nitric oxide synthase. The potassium channel activators,the nitric oxide donors, and the vasoactive agents can be administeredseparately or as components of the same composition in one or morepharmaceutically acceptable carriers.

The present invention also provides methods using the compounds andcompositions described herein to prevent or treat cardiovasculardisorders, such as congestive heart failure and myocardial ischemia,especially angina pectoris and arrhythmia; cerebrovascular disorders,including those associated with cerebral ischemia; hypertension; asthma;baldness; urinary incontinence; epilepsy; sleep disorders;gastrointestinal disorders; migraines; irritable bowel syndrome andsensitive skin, by administering to a patient in need thereof atherapeutically effective amount of at least one of the compounds and/orcompositions described herein. In these methods, the potassium channelactivators that are optionally nitrosated and/or nitrosylated, nitricoxide donors and vasoactive agents can be administered separately or ascomponents of the same composition in one or more pharmaceuticallyacceptable carriers.

These and other aspects of the present invention are described in detailherein.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is the synthetic scheme for the preparation of a nitritecontaining N-amide of Formula (I).

FIG. 2 is the synthetic scheme for the preparation of a nitrosothiolcontaining N-amide of Formula (I).

FIG. 3 is the synthetic scheme for the preparation of a nitritecontaining N-cyano-N′substituted-carboximidamide of Formula (I).

FIG. 4 is the synthetic scheme for the preparation of a nitrosothiolcontaining N-cyano-N′substituted-carboximidamide of Formula (I).

FIG. 5 is the synthetic scheme for the preparation of a nitritecontaining N-cyano-N′substituted-carboximidamide of Formula (I).

FIG. 6 is the synthetic scheme for the preparation of a nitrosothiolcontaining N-cyano-N′substituted-carboximidamide of Formula (I).

FIG. 7 is the synthetic scheme for the preparation of a nitritecontaining acyl group of Formula (II).

FIG. 8 is the synthetic scheme for the preparation of a nitrosothiolcontaining acyl group of Formula (II).

FIG. 9 is the synthetic scheme for the preparation of a nitritecontaining acyl group of Formula (III).

FIG. 10 is the synthetic scheme for the preparation of a nitrosothiolcontaining acyl group of Formula (III).

FIG. 11 is the synthetic scheme for the preparation of a nitritecontaining acyl group of Formula (IV).

FIG. 12 is the synthetic scheme for the preparation of a nitrosothiolcontaining acyl group of Formula (IV).

FIG. 13 is the synthetic scheme for the preparation of a nitritecontaining acyl group of Formula (V).

FIG. 14 is the synthetic scheme for the preparation of a nitrosothiolcontaining acyl group of Formula (V).

FIG. 15 is the synthetic scheme for the preparation of a nitritecontaining acyl group of Formula (VI).

FIG. 16 is the synthetic scheme for the preparation of a nitrosothiolcontaining acyl group of Formula (VI).

DETAILED DESCRIPTION OF THE INVENTION

As used throughout the disclosure, the following terms, unless otherwiseindicated, shall be understood to have the following meanings.

“Potassium channel activator” refers to any compound that results in theopening of the potassium channel such that the permeability of potassiumis increased, thereby resulting in hyperpolarization and relaxation ofsmooth muscles.

“Patient” refers to animals, preferably mammals, more preferably humans,and includes children and adults.

“Gastrointestinal disorder” refers to any disease or disorder of theupper gastrointestinal tract of a patient including, for example, pepticulcers, stress ulcers, gastric hyperacidity, dyspepsia, gastroparesis,Zollinger-Ellison syndrome, gastroesophageal reflux disease, short-bowel(anastomosis) syndrome, hypersecretory states associated with systemicmastocytosis or basophilic leukemia and hyperhistaminemia, and bleedingpeptic ulcers that result, for example, from neurosurgery, head injury,severe body trauma or burns.

“Upper gastrointestinal tract” refers to the esophagus, the stomach, theduodenum and the jejunum.

“Ulcers” refers to lesions of the upper gastrointestinal tract liningthat are characterized by loss of tissue. Such ulcers include gastriculcers, duodenal ulcers and gastritis.

“Thromboxane inhibitor” refers to any compound that reversibly orirreversibly inhibits thromboxane synthesis, and includes compoundswhich are the so-called thromboxane A₂ receptor antagonists, thromboxaneA₂ antagonists, thromboxane A₂/prostaglandin endoperoxide antagonists,thromboxane receptor (TP) antagonists, thromboxane antagonists,thromboxane synthase inhibitors, and dual acting thromboxane synthaseinhibitors and thromboxane receptor antagonists.

“Thromboxane A₂ receptor antagonist” refers to any compound thatreversibly or irreversibly blocks the activation of any thromboxane A₂receptor.

“Thromboxane synthase inhibitor” refers to any compound that reversiblyor irreversibly inhibits the enzyme thromboxane synthesis therebyreducing the formation of thromboxane A₂.

“Dual acting thromboxane receptor antagonist and thromboxane synthaseinhibitor” refers to any compound that simultaneously acts as athromboxane A₂ receptor antagonist and a thromboxane synthase inhibitor.

“Topical” refers to the delivery of a compound by passage through theskin and into the blood stream and includes transdermal delivery.

“Transmucosal” refers to delivery of a compound by passage of thecompound through the mucosal tissue and into the blood stream.

“Transurethral” or “intraurethral” refers to delivery of a drug into theurethra, such that the drug contacts and passes through the wall of theurethra and enters into the blood stream.

“Penetration enhancement” or “permeation enhancement” refers to anincrease in the permeability of the skin or mucosal tissue to a selectedpharmacologically active compound such that the rate at which thecompound permeates through the skin or mucosal tissue is increased.

“Carriers” or “vehicles” refers to carrier materials suitable forcompound administration and include any such material known in the artsuch as, for example, any liquid, gel, solvent, liquid diluent,solubilizer, or the like, which is non-toxic and which does not interactwith any components of the composition in a deleterious manner.

“Nitric oxide adduct” or “NO adduct” refers to compounds and functionalgroups which, under physiological conditions, can donate, release and/ordirectly or indirectly transfer any of the three redox forms of nitrogenmonoxide (NO⁺, NO⁻, NO.), such that the biological activity of thenitrogen monoxide species is expressed at the intended site of action.

“Nitric oxide releasing” or “nitric oxide donating” refers to methods ofdonating, releasing and/or directly or indirectly transferring any ofthe three redox forms of nitrogen monoxide (NO⁺, NO−, NO.), such thatthe biological activity of the nitrogen monoxide species is expressed atthe intended site of action.

“Nitric oxide donor” or “NO donor” refers to compounds that donate,release and/or directly or indirectly transfer a nitrogen monoxidespecies, and/or stimulate the endogenous production of nitric oxide orendothelium-derived relaxing factor (EDRF) in vivo and/or elevateendogenous levels of nitric oxide or EDRF in vivo. “NO donor” alsoincludes compounds that are substrates for nitric oxide synthase.

“Alkyl” refers to a lower alkyl group, a haloalkyl group, an alkenylgroup, an alkynyl group, a bridged cycloalkyl group, a cycloalkyl groupor a heterocyclic ring, as defined herein.

“Lower alkyl” refers to branched or straight chain acyclic alkyl groupcomprising one to about ten carbon atoms (preferably one to about eightcarbon atoms, more preferably one to about six carbon atoms). Exemplarylower alkyl groups include methyl, ethyl, n-propyl, isopropyl, n-butyl,isobutyl, sec-butyl, t-butyl, pentyl, neopentyl, iso-amyl, hexyl, octyl,and the like.

“Haloalkyl” refers to a lower alkyl group, an alkenyl group, an alkynylgroup, a bridged cycloalkyl group, a cycloalkyl group or a heterocyclicring, as defined herein, to which is appended one or more halogens, asdefined herein. Exemplary haloalkyl groups include trifluoromethyl,chloromethyl, 2-bromobutyl, 1-bromo-2-chloro-pentyl, and the like.

“Alkenyl” refers to a branched or straight chain C₂-C₁₀ hydrocarbon(preferably low a C₂-C₈ hydrocarbon, more preferably a C₂-C₆hydrocarbon) which can comprise one or more carbon-carbon double bonds.Exemplary alkenyl groups include propylenyl, buten-1-yl, isobutenyl,penten-1-yl, 2,2-methylbuten-1-yl, 3-methylbuten-1-yl, hexan-1-yl,hepten-1-yl, octen-1-yl, and the like.

“Alkynyl” refers to an unsaturated acyclic C₂-C₁₀ hydrocarbon(preferably a C_(2-C) ₈ hydrocarbon, more preferably a C₂-C₆hydrocarbon) which can comprise one or more carbon-carbon triple bonds.Exemplary alkynyl groups include ethynyl, propynyl, butyn-1-yl,butyn-2-yl, pentyl-1-yl, pentyl-2-yl, 3-methylbutyn-1-yl, hexyl-1-yl,hexyl-2-yl, hexyl-3-yl, 3,3-dimethyl-butyn-1-yl, and the like.

“Bridged cycloalkyl” refers to two or more cycloalkyl groups,heterocyclic groups, or a combination thereof fused via adjacent ornon-adjacent atoms. Bridged cycloalkyl groups can be unsubstituted orsubstituted with one, two or three substituents independently selectedfrom alkyl, alkoxy, amino, alkylamino, dialkylamino, hydroxy, halo,carboxyl, alkylcarboxylic acid, aryl, amidyl, ester, alkylcarboxylicester, carboxamido, alkylcarboxamido, oxo and nitro. Exemplary bridgedcycloalkyl groups include adamantyl, decahydronapthyl, quinuclidyl,2,6-dioxabicyclo[3.3.0]octane, 7-oxabycyclo[2.2.1]heptyl,8-azabicyclo[3,2,1]oct-2-enyl and the like.

“Cycloalkyl” refers to a saturated or unsaturated cyclic hydrocarboncomprising from about 3 to about 8 carbon atoms. Cycloalkyl groups canbe unsubstituted or substituted with one, two or three substituentsindependently selected from alkyl, alkoxy, amino, alkylamino,dialkylamino, arylamino, diarylamino, alkylarylamino, aryl, amidyl,ester, hydroxy, halo, carboxyl, alkylcarboxylic acid, alkylcarboxylicester, carboxamido, alkylcarboxamido, oxo and nitro. Exemplarycycloalkyl groups include cyclopropyl, cyclobutyl, cyclopentyl,cyclohexyl, cyclohexenyl, cyclohepta,1,3-dienyl, and the like.

“Heterocyclic ring or group” refers to a saturated, unsaturated, cyclicor aromatic or polycyclic hydrocarbon group having about 3 to about 12carbon atoms (preferably about 4 to about 6 carbon atoms) where 1 toabout 4 carbon atoms are replaced by one or more nitrogen, oxygen and/orsulfur atoms. Sulfur maybe in the thio, sulfinyl or sulfonyl oxidationstate. The heterocyclic ring or group can be fused to an aromatichydrocarbon group. Heterocyclic groups can be unsubstituted orsubstituted with one, two or three substituents independently selectedfrom alkyl, alkoxy, amino, alkylamino, dialkylamino, arylamino,diarylamino, alkylarylamino, hydroxy, oxo, thial, halo, carboxyl,carboxylic ester, alkylcarboxylic acid, alkylcarboxylic ester, aryl,arylcarboxylic acid, arylcarboxylic ester, amidyl, ester, carboxamido,alkylcarboxamido, arylcarboxamido, sulfonic acid, sulfonic ester,sulfonamido and nitro. Exemplary heterocyclic groups include pyrrolyl,3-pyrrolinyl, 4,5,6-trihydro-2H-pyranyl, pyridinyl,1,4-dihydropyridinyl, pyrazolyl, triazolyl, pyrimidinyl, pyridazinyl,oxazolyl, thiazolyl, imidazolyl, indolyl, thiophenyl, furanyl,tetrhydrofuranyl, tetrazolyl, 2-pyrrolinyl, 3-pyrrolinyl, pyrrolindinyl,oxazolindinyl 1,3-dioxolanyl, 2,6-dioxabicyclo[3,3,0]octanyl,2-imidazonlinyl, imidazolindinyl, 2-pyrazolinyl, pyrazolidinyl,isoxazolyl, isothiazolyl, 1,2,3-oxadiazolyl, 1,2,3-triazolyl,1,3,4-thiadiazolyl, 2H-pyranyl, 4H-pyranyl, piperidinyl, 1,4-dioxanyl,morpholinyl, 1,4-dithianyl, thiomorpholinyl, pyrazinyl, piperazinyl,1,3,5-triazinyl, 1,3,5-trithianyl, benzo(b)thiophenyl, benzimidazolyl,quinolinyl, and the like.

“Heterocyclic compounds” refer to mono- and polycyclic compoundscomprising at least one aryl or heterocyclic ring.

“Aryl” refers to a monocyclic, bicyclic, carbocyclic or heterocyclicring system comprising one or two aromatic rings. Exemplary aryl groupsinclude phenyl, pyridyl, napthyl, quinoyl, tetrahydronaphthyl, furanyl,indanyl, indenyl, indoyl, and the like. Aryl groups (including bicylicaryl groups) can be unsubstituted or substituted with one, two or threesubstituents independently selected from alkyl, alkoxy, amino,alkylamino, dialkylamino, arylamino, diarylamino, alkylarylamino,hydroxy, carboxyl, carboxylic ester, alkylcarboxylic acid,alkylcarboxylic ester, aryl, arylcarboxylic acid, arylcarboxylic ester,alkylcarbonyl, arylcarbonyl, amidyl, ester, carboxamido,alkylcarboxamido, carbomyl, sulfonic acid, sulfonic ester, sulfonamidoand nitro. Exemplary substituted aryl groups include tetrafluorophenyl,pentafluorophenyl, sulfonamide, alkylsulfonyl, arylsulfonyl, and thelike.

“Alkylaryl” refers to an alkyl group, as defined herein, to which isappended an aryl group, as defined herein. Exemplary alkylaryl groupsinclude benzyl, phenylethyl, hydroxybenzyl, fluorobenzyl,fluorophenylethyl, and the like.

“Arylalkyl” refers to an aryl radical, as defined herein, attached to analkyl radical, as defined herein.

“Cycloalkylalkyl” refers to a cycloalkyl radical, as defined herein,attached to an alkyl radical, as defined herein.

“Heterocyclicalkyl” refers to a heterocyclic ring radical, as definedherein, attached to an alkyl radical, as defined herein.

“Cycloalkenyl” refers to an unsaturated cyclic hydrocarbon having about3 to about 10 carbon atoms (preferably about 3 to about 8 carbon atoms,more preferably about 3 to about 6 carbon atoms) comprising one or morecarbon-carbon double bonds.

“Arylheterocyclic ring” refers to a bi- or tricyclic ring comprised ofan aryl ring, as defined herein, appended via two adjacent carbon atomsof the aryl ring to a heterocyclic ring, as defined herein. Exemplaryarylheterocyclic rings include dihydroindole,1,2,3,4-tetra-hydroquinoline, and the like.

“Alkoxy” refers to R₅₀O—, wherein R₅₀ is an alkyl group, as definedherein. Exemplary alkoxy groups include methoxy, ethoxy, t-butoxy,cyclopentyloxy, and the like.

“Arylalkoxy or alkoxyaryl” refers to an alkoxy group, as defined herein,to which is appended an aryl group, as defined herein. Exemplaryarylalkoxy groups include benzyloxy, phenylethoxy, chlorophenylethoxy,and the like.

“Alkoxyalkyl” refers to an alkoxy group, as defined herein, appended toan alkyl group, as defined herein. Exemplary alkoxyalkyl groups includemethoxymethyl, methoxyethyl, isopropoxymethyl, and the like.

“Alkoxyhaloalkyl” refers to an alkoxy group, as defined herein, appendedto a haloalkyl group, as defined herein. Exemplary alkoxyhaloalkylgroups include 4-methoxy-2-chlorobutyl and the like.

“Cycloalkoxy” refers to R₅₄O—, wherein R₅₄ is a cycloalkyl group or abridged cycloalkyl group, as defined herein. Exemplary cycloalkoxygroups include cyclopropyloxy, cyclopentyloxy, cyclohexyloxy, and thelike.

“Haloalkoxy” refers to a haloalkyl group, as defined herein, to which isappended an alkoxy group, as defined herein. Exemplary haloalkyl groupsinclude 1,1,1-trichloroethoxy, 2-bromobutoxy, and the like.

“Hydroxy” refers to —OH.

“Oxo ” refers to ═O.

“Oxy” refers to —O⁻R₇₇ ⁺ wherein R₇₇ is an organic or inorganic cation.

“Organic cation” refers to a positively charged organic ion. Exemplaryorganic cations include alkyl substituted ammonium cations, and thelike.

“Inorganic cation” refers to a positively charged metal ion. Exemplaryinorganic cations include metal cations such as for example, sodium,potassium, calcium, and the like.

“Hydroxyalkyl” refers to a hydroxy group, as defined herein, appended toan alkyl group, as defined herein.

“Amino” refers to —NH₂.

“Nitrate” refers to —O—NO₂.

“Nitrite” refers to —O—NO.

“Thionitrate” refers to —S—NO₂.

“Thionitrite” and “nitrosothiol” refer to —S—NO.

“Nitro” refers to the group —NO₂ and “nitrosated” refers to compoundsthat have been substituted therewith.

“Nitroso” refers to the group —NO and “nitrosylated” refers to compoundsthat have been substituted therewith.

“Nitrile” and “cyano” refer to —CN.

“Halogen” or “halo” refers to iodine (I), bromine (Br), chlorine (Cl),and/or fluorine (F).

“Alkylamino” refers to R₅₀NH—, wherein R₅₀ is an alkyl group, as definedherein. Exemplary alkylamino groups include methylamino, ethylamino,butylamino, cyclohexylamino, and the like.

“Arylamino” refers to R₅₅NH—, wherein R₅₅ is an aryl group, as definedherein.

“Dialkylamino” refers to R₅₀R₅₂N—, wherein R₅₀ and R₅₂ are eachindependently an alkyl group, as defined herein. Exemplary dialkylaminogroups include dimethylamino, diethylamino, methyl propargylamino, andthe like.

“Diarylamino” refers to R₅₅R₆₀N—, wherein R₅₅ and R₆₀ are eachindependently an aryl group, as defined herein.

“Alkylarylamino” refers to R₅₀R₅₅N—, wherein R₅₀ is an alkyl group, asdefined herein, and R₅₅ is an aryl group, as defined herein.

“Aminoalkyl” refers to an amino group, an alkylamino group, adialkylamino group, an arylamino group, a diarylamino group, analkylarylamino group or a heterocyclic ring, as defined herein, to whichis appended an alkyl group, as defined herein.

“Aminoaryl” refers to an amino group, an alkylamino group, adialkylamino group, an arylamino group, a diarylamino group, analkylarylamino group or a heterocyclic ring, as defined herein, to whichis appended an aryl group, as defined herein.

“Thio” refers to —S—.

“Sulfinyl” refers to —S(O)—.

“Methanthial” refers to —C(S)—.

“Thial” refers to ═S.

“Sulfonyl” refers to —S(O)₂ ⁻.

“Sulfonic acid” refers to —S(O)₂OR₇₆, wherein R₇₆ is a hydrogen, anorganic cation or an inorganic cation.

“Alkylsulfonic acid” refers to a sulfonic acid group, as defined herein,appended to an alkyl group, as defined herein.

“Arylsulfonic acid” refers to an sulfonic acid group, as defined herein,appended to an aryl group, as defined herein

“Sulfonic ester” refers to —S(O)₂OR₅₈, wherein R₅₈ is an alkyl group, anaryl group, an alkylaryl group or an aryl heterocyclic ring, as definedherein.

“Sulfonamido” refers to —S(O)₂—N(R₅₁)(R₅₇), wherein R₅₁ and R₅₇ are eachindependently a hydrogen atom, an alkyl group, an aryl group, analkylaryl group, or an arylheterocyclic ring, as defined herein, or R₅₁and R₅₇ taken together are a heterocyclic ring, a cycloalkyl group or abridged cycloalkyl group, as defined herein.

“Alkylsulfonamido” refers to a sulfonamido group, as defined herein,appended to an alkyl group, as defined herein.

“Arylsulfonamido” refers to a sulfonamido group, as defined herein,appended to an aryl group, as defined herein.

“Alkylthio” refers to R₅₀S—, wherein R₅₀ is an alkyl group, as definedherein.

“Arylthio” refers to R₅₅S—, wherein R₅₅ is an aryl group, as definedherein.

“Cycloalkylthio” refers to R₅₄S—, wherein R₅₄ is a cycloalkyl group or abridged cycloalkyl group, as defined herein. Exemplary cycloalkylthiogroups include cyclopropylthio, cyclopentylthio, cyclohexylthio, and thelike.

“Alkylsulfinyl” refers to R₅₀—S(O)—, wherein R₅₀ is an alkyl group, asdefined herein.

“Alkylsulfonyl” refers to R₅₀—S(O)₂—, wherein R₅₀ is an alkyl group, asdefined herein.

“Arylsulfinyl” refers to R₅₅—S(O)—, wherein R₅₅ is an aryl group, asdefined herein.

“Arylsulfonyl” refers to R₅₅—S(O)₂—, wherein R₅₅ is an aryl group, asdefined herein.

“Amidyl” refers to R₅₁C(O)N(R₅₇)— wherein R₅₁ and R₅₇ are eachindependently a hydrogen atom, an alkyl group, an aryl group, analkylaryl group, or an arylheterocyclic ring, as defined herein.

“Ester” refers to R₅₁C(O)O— wherein R₅₁ is a hydrogen atom, an alkylgroup, an aryl group, an alkylaryl group, or an arylheterocyclic ring,as defined herein.

“Carbamoyl” refers to —O—C(O)N(R₅₁)(R₅₇), wherein R₅₁ and R₅₇ are eachindependently a hydrogen atom, an alkyl group, an aryl group, analkylaryl group or an arylheterocyclic ring, as defined herein, or R₅₁and R₅₇ taken together are a heterocyclic ring, a cycloalkyl group or abridged cycloalkyl group, as defined herein.

“Carbamate” refers to R₅₁O—C(O)N(R₅₇), wherein R₅₁ and R₅₇ are eachindependently a hydrogen atom, an alkyl group, an aryl group, analkylaryl group or an arylheterocyclic ring, as defined herein, or R₅₁and R₅₇ taken together are a heterocyclic ring, a cycloalkyl group or abridged cycloalkyl group, as defined herein.

“Carboxyl” refers to —C(O)OR₇₆, wherein R₇₆ is a hydrogen, an organiccation or an inorganic cation, as defined herein.

“Carbonyl” refers to —C(O)—.

“Alkylcarbonyl” or “alkanoyl” refers to R₅₀—C(O)—, wherein R₅₀ is analkyl group, as defined herein.

“Arylcarbonyl” or “aroyl” refers to R₅₅—C(O)—, wherein R₅₅ is an arylgroup, as defined herein.

“Carboxylic ester” refers to —C(O)OR₅₈, wherein R₅₈ is an alkyl group,an aryl group, an alkylaryl group or an aryl heterocyclic ring, asdefined herein.

“Alkylcarboxylic acid” and “alkylcarboxyl” refer to an alkyl group, asdefined herein, appended to a carboxyl group, as defined herein.

“Alkylcarboxylic ester” refers to an alkyl group, as defined herein,appended to a carboxylic ester group, as defined herein.

“Arylcarboxylic acid” refers to an aryl group, as defined herein,appended to a carboxyl group, as defined herein.

“Arylcarboxylic ester” and “arylcarboxyl” refer to an aryl group, asdefined herein, appended to a carboxylic ester group, as defined herein.

“Carboxamido” refers to —C(O)N(R₅₁)(R₅₇), wherein R₅₁ and R₅₇ are eachindependently a hydrogen atom, an alkyl group, an aryl group, analkylaryl group or an arylheterocyclic ring, as defined herein, or R₅₁and R₅₇ taken together with the nitrogen to which they are attached forma heterocyclic ring, a cycloalkyl group or a bridged cycloalkyl group,as defined herein.

“Alkylcarboxamido” refers to an alkyl group, as defined herein, appendedto a carboxamido group, as defined herein.

“Arylcarboxamido” refers to an aryl group, as defined herein, appendedto a carboxamido group, as defined herein.

“Urea” refers to —N(R₅₉)—C(O)N(R₅₁)(R₅₇) wherein R₅₁, R₅₇, and R₅₉ areeach independently a hydrogen atom, an alkyl group, an aryl group, analkylaryl group, or an arylheterocyclic ring, as defined herein, or R₅₁and R₅₇ taken together with the nitrogen to which they are attached forma heterocyclic ring, as defined herein.

“Phosphoryl” refers to —P(R₇₀)(R₇₁)(R₇₂), wherein R₇₀ is a lone pair ofelectrons, sulfur or oxygen, and R₇₁ and R₇₂ are each independently acovalent bond, a hydrogen, a lower alkyl, an alkoxy, an alkylamino, ahydroxy or an aryl, as defined herein.

The term “sexual dysfunction” generally includes any sexual dysfunctionin a patient, including an animal, preferably a mammal, more preferablya human. The patient can be male or female. Sexual dysfunctions caninclude, for example, sexual desire disorders, sexual arousal disorders,orgasmic disorders and sexual pain disorders. Female sexual dysfunctionrefers to any female sexual dysfunction including, for example, sexualdesire disorders, sexual arousal dysfunctions, orgasmic dysfunctions,sexual pain disorders, dyspareunia, and vaginismus. The female can bepre-menopausal or menopausal. Sexual dysfunction can be caused, forexample, by pregnancy, menopause, cancer, pelvic surgery, chronicmedical illness or medications. Male sexual dysfunction refers to anymale sexual dysfunctions including, for example, male erectiledysfunction and impotence.

The present invention is directed to the treatment and/or prevention ofsexual dysfunctions in patients, including males and females, byadministering the compounds and compositions described herein. Thepresent invention is also directed to enhancing sexual responses inpatients, including males and females, by administering the compoundsand/or compositions described herein. The novel compounds and novelcompositions of the present invention are described in more detailherein.

Potassium channel activators have the ability to open potassium channelsin a variety of cells. Opening of the potassium channel leads tohyperpolarization of the surface membrane with consequent closure ofvoltage-dependent ion channels and reduction of free intracellularpotassium ions. The potassium channel activators have a high affinityfor potassium channels of vascular smooth muscle. Vasodilation and areduction in systemic vascular resistance are their predominantpharmacological effects. Coronary, cerebral, airway and corpuscavernosum arteries are very sensitive to potassium channelactivator-induced dilation. The potassium channel activator, nicorandil,is marketed by Rhone-Poulenc-Rorer under the trademark ICOREL™.Holmquist et al, Acta. Physiol. Scand., 138:463-469 (1990) investigatedthe effects of pinacidil on isolated human corpus cavernosum tissue, andtheir results suggest that pinacidil is effective in relaxing thetissue, probably by increasing the potassium permeability and subsequenthyperpolarization.

Contemplated potassium channel activators for use in the presentinvention include all those known in the art, such as, for example,nicorandil, pinacidil, cromakalim (BRL 34915), aprikalim, bimakalim,emakalim, lemakalim, minoxidil, diazoxide,9-chloro-7-(2-chlorophenyl)-5H-pyrimido(5,4,-d)(2)-benzazepine, Ribi,CPG-11952, CGS9896, ZD 6169, diazixide, Bay X 9227, P1075, Bay X 9228,SDZ PCO 400, WAY-120,491, WAY-120,129, Ro 31-6930, SR 44869, BRL 38226,S 0121, SR 46142A, CGP 42500, SR 44994, artilide fumarate, lorazepam,temazepam, rilmazafone, nimetazepam, midazolam, lormetazepam,loprazolam, ibutilide fumarate, haloxazolam, flunitrazepam, estazolam,doxefazepam, clonazepam, cinolazepam and brotizolam. Preferred potassiumchannel activators for use in the methods described herein (particularlyfor the treatment and/or prevention of sexual dysfunctions) arenicorandil, pinacidil, cromakalim (BRL 34915), aprikalim, bimakalim,emakalim and lemakalim. Nicorandil, pinacidil, cromakalim and minoxidilare the most preferred potassium channel activators.

Sources of information for the above compounds include Goodman andGilman, The Pharmacological Basis of Therapeutics (9th Ed.),McGraw-Hill, Inc. (1996), The Physician's Desk Reference (49th Ed.),Medical Economics (1995), Drug Facts and Comparisons (1993 Ed), Factsand Comparisons (1993), Merck Index on CD-ROM, Twelfth Edition, Version12:1, (1996), STN Express, file phar and file registry, the disclosuresof each of which are incorporated herein by reference in their entirety.

In addition to the specific potassium channel activators describedherein, the potassium channel activators for use in the presentinvention generally include compounds of Formula (A), Formula (B),Formula (C), Formula (D), Formula (E) and Formula (F).

The potassium channel activator of Formula (A) is:

wherein

R₁ is

wherein

R₂ is a hydrogen atom or a halogen atom;

B is oxygen or —N—CN; and

D is A or J;

A is—W_(a)—E_(b)—(C(R_(e))(R_(f)))_(p)—E_(c)—(C(R_(e))(R_(f)))_(x)—W_(d)—(C(R_(e))(R_(f)))_(y)—W_(i)—E_(j)—W_(g)—(C(R_(e))(R_(f)))_(z)—ONO₂;

J is—W_(a)—E_(b)(C(R_(e))(R_(f)))_(p)—E_(c)—(C(R_(e))(R_(f)))_(x)—W_(d)—(C(R_(e))(R_(f)))_(y)—W_(i)—E_(j)—W_(g)—(C(R_(e))(R_(f))(R_(h)))_(z);

a, b, c, d, g, i and j are each independently an integer from 0 to 3;

p, x, y and z are each independently an integer from 0 to 10;

W at each occurrence is independently —C(O)—, —C(S)—, —T—,—(C(R_(e))(R_(f)))_(h)—, an alkyl group, an aryl group, a heterocyclicring, an arylheterocyclic ring, or —(CH₂CH₂O)_(q)—;

E at each occurrence is independently —T—, an alkyl group, an arylgroup, —(C(R_(e))(R_(f)))_(h)—, a heterocyclic ring, an arylheterocyclicring, or —(CH₂CH₂O)_(q)—;

h is an integer form 1 to 10;

q is an integer from 1 to 5;

R_(e), R_(f) and R_(h) are each independently a hydrogen, an alkyl, acycloalkoxy, a halogen, a hydroxy, an hydroxyalkyl, an alkoxyalkyl, anarylheterocyclic ring, an alkylaryl, a cycloalkylalkyl, aheterocyclicalkyl, an alkoxy, a haloalkoxy, an amino, an alkylamino, adialkylamino, an arylamino, a diarylamino, an alkylarylamino, analkoxyhaloalkyl, a haloalkoxy, a sulfonic acid, a sulfonic ester, analkylsulfonic acid, an arylsulfonic acid, an arylalkoxy, an alkylthio,an arylthio, a cycloalkylthio, a cycloalkenyl, a cyano, an aminoalkyl,an aminoaryl, an aryl, an arylalkyl, an alkylaryl, a carboxamido, aalkylcarboxamido, an arylcarboxamido, an amidyl, a carboxyl, acarbamoyl, an alkylcarboxylic acid, an arylcarboxylic acid, analkylcarbonyl, an arylcarbonyl, an ester, a carboxylic ester, analkylcarboxylic ester, an arylcarboxylic ester, a haloalkoxy, asulfonamido, an alkylsulfonamido, an arylsulfonamido, a sulfonic ester,a urea, a phosphoryl, a nitro, or R_(e) and R_(f) or R_(e), R_(f) andR_(h) taken together with the carbons to which they are attached form acarbonyl, a methanthial, a heterocyclic ring, a cycloalkyl group or abridged cycloalkyl group;

k is an integer from 1 to 3;

T at each occurrence is independently a covalent bond, a carbonyl, anoxygen, —S(O)_(o)— or —N(R_(a))R_(i)—;

o is an integer from 0 to 2;

R_(a) is a lone pair of electrons, a hydrogen or an alkyl group;

R_(i) is a hydrogen, an alkyl, an aryl, an alkylcarboxylic acid, anarylcarboxylic acid, an alkylcarboxylic ester, an arylcarboxylic ester,an alkylcarboxamido, an arylcarboxamido, an alkylaryl, an alkylsulfinyl,an alkylsulfonyl, an arylsulfinyl, an arylsulfonyl, a sulfonamido, acarboxamido, a carboxylic ester, an amino alkyl, an amino aryl.

In cases where R_(e), R_(f) and R_(h) are a heterocyclic ring or takentogether R_(e) and R_(f) or R_(e), R_(f) and R_(h) are a heterocyclicring, then R_(i) can be a substituent on any disubstituted nitrogencontained within the radical where R_(i) is as defined herein.

In cases where multiple designations of variables which reside insequence are chosen as a “covalent bond” or the integer chosen is 0, theintent is to denote a single covalent bond connecting one radical toanother. For example, E₀ would denote a covalent bond, while E₂ denotes(E—E) and (C(R_(e))(R_(f)))₂ denotes —C(R_(e))(R_(f))—C(R_(e))(R_(f))—,where R_(e) and R_(f) at each occurrence are each independently selectedfrom those moieties defined herein.

The potassium channel activator of Formula (B) is:

wherein

R₃ is a hydrogen, an alkyl, an aryl, an alkylaryl;

D₁ is a hydrogen atom or an alkyl group; and

G is:

wherein R₄, R₅, and R₆ are each independently a hydrogen, a halogen, ahydroxy, a lower alkyl, an alkoxy, a nitrile, a nitrite, a carboxyamido,a carboxylic ester, an alkylsulfinyl, an arylsulfinyl, an aminoalkyl, analkylthio, an arylthio; or R₅ and R₆ taken together are a group whichforms a ring with the two carbon atoms to which they are attached,wherein the group is —S(O)_(t)—(CH₂)_(r)—CH₂—, —C(O)Z—(CH₂)_(o)—CH₂—, or—C(O)—CH₂—(CH₂)_(o)—Z—;

t is an integer of 1 or 2;

r is an integer from 1 to 3;

Z is oxygen, NR₇ or CH₂;

R₇ is hydrogen or R₃; and

o is as defined herein.

The potassium channel activator of Formula (C) is:

wherein

X —(CH₂)_(a)— or oxygen;

Y is:

R₇ and R₈ are each independently a hydrogen, an alkylcarbonyl, analkoxycarbonyl, a heterocyclic ring, an ester, a nitro, a cyano, a halo,a haloalkyl, an alkylsulphinyl, an alkylsulphonyl, a sulfonic ester, anamidyl, a carbamate, a formyl, a sulfonamido, or a carboxamido;

R₉ is an aryl or a heterocyclic ring;

R₁₀ is a carboxylic ester, a carboxylic acid, a carboxamido, a urea, athiourea, an amidyl, a sulfamoyl, a hydroxyalkyl, —C(O)OD,—N(R₅₉)(C═NCN)NR₅₁R₅₇, —N(R₅₉)(C═NCN)SR₁₂, —N(R₅₉)(C═NCN)OR₁₂,—P(O)(OR₅₀)₂, —P(O)(O(CH₂)_(k′)O), —SR₁₁, —S(O)R₁₁, —S(O)₂R₁₁, —OR₁₁, acyano, a heterocyclic ring, a pyridine N-oxide or—C(NR₅₁R₅₇)═CH—C(O)R₅₉;

R₁₁ is a hydrogen, an alkyl, an aryl, an arylalkyl, a cycloalkyl, orcycloalkylalkyl;

R₁₂ is an alkyl, an aryl, an alkylaryl, or an arylheterocyclic ring;

R₁₃ is aryl, a heterocyclic ring, a cycloalkyl

X₁ is an oxygen, a sulfur, or —NH—;

X₂ is a hydrogen or an alkyl group;

X₃ is oxygen or sulfur;

k′ is an interger from 2 to 4;

a′ and b′ are each independently an integer from 0 to 3; and

a, D, R₅₀, R₅₁, R₅₇ and R₅₉ are as defined herein.

The potassium channel activator of Formula (D) is:

The potassium channel activator of Formula (E) is:

wherein,

R₁₄ and R₁₅ are each independently a lower alkyl, a lower haloalkyl orR₁₄ and R₁₅ together with the carbon to which they are attached form acyclic haloalkyl group;

A₁—B₁ is —NHC(O)—, —OCH₂—, —SCH₂—NHCH₂, —CH═CH—, or —CH═CH—; and

Y₁ is an aryl group.

The potassium channel activator of Formula (F) is:

wherein,

R₁₆ and R₁₇ are each independently a lower alkyl, a lower haloalkyl orR₁₆ and R₁₇ together with the carbon to which they are attached form acyclic haloalkyl group;

Y₃ is an sp²-hybridized atom and Y₂, Y₃, and Y₄ together with the carbonatoms to which they are attached form a 5- or 6-membered heterocyclicring;

R₁₈ and R₁₉ are each independently a hydrogen, a nitro, a cyano, a halo,a haloalkyl, an alkylsulfonyl, or an aryl, with the proviso that eitherR₁₈ or R₁₉ must be a hydrogen but that both R₁₈ and R₁₉ cannot be ahydrogen.

Other potassium channel activators that can be used in the presentinvention include those described in U.S. Pat. Nos. 4,057,636,4,200,640, 5,166,347, 5,223,508, 5,262,419 and 5,869,509 the disclosuresof each of which are incorporated by reference herein. in theirentirety. Methods for making potassium channel activators, includingthose of Formula (A), Formula (B), Formula (C), Formula (D), Formula (E)and Formula (F) are known in the art, and are described, for example, inU.S. Pat. Nos. 3,382,247, 3,644,364, 4,057,636, 4,200,640, 5,140,031,5,166,347, 5,206,252, 5,223,508, 5,232,938, 5,262,419, 5,393,771,5,401,758, 5,411,973, 5,416,097, 5,482,969, 5,504,089, 5,677,324,5,679,706, 5,693,639, 5,837,702 and 5,900,432 and in EP 0 076 075 A1, EP0 107 423 A1, EP 0 120 427 A1, EP 0 120 428 A1 and EP 0 107 423 A1, thedisclosures of each of which are incorporated by reference herein intheir entirety.

The present invention also describes novel nitrosated and/ornitrosylated potassium channel activators of Formula (I):

wherein

R₁ is:

wherein

R₂ is a hydrogen atom or a halogen atom;

B is oxygen or —N—CN;

D₂ is Q or K;

Q is —NO or —NO₂;

K is—W_(a)—E_(b)—(C(R_(e))(R_(f)))_(p)—E_(c)—(C(R_(e))(R_(f)))_(x)—W_(d)—(C(R_(e))(R_(f)))_(y)—W_(i)—E_(j)—W_(g)—(C(R_(e))(R_(f)))_(z)—T—Q;

a, b, c, d, g, i and j are each independently an integer from 0 to 3;

p, x, y and z are each independently an integer from 0 to 10;

W at each occurrence is independently —C(O)—, —C(S)—, —T—,—(C(R_(e))(R_(f)))_(h)—, an alkyl group, an aryl group, a heterocyclicring, an arylheterocyclic ring, or —(CH₂CH₂O)_(q)—;

E at each occurrence is independently —T—, an alkyl group, an arylgroup, —(C(R_(e))(R_(f)))_(h)—, a heterocyclic ring, an arylheterocyclicring, or (CH₂CH₂O)_(q);

h is an integer from 1 to 10;

q is an integer from 1 to 5;

R_(e) and R_(f) are each independently a hydrogen, an alkyl, acycloalkoxy, a halogen, a hydroxy, an hydroxyalkyl, an alkoxyalkyl, anarylheterocyclic ring, an alkylaryl, a cycloalkylalkyl, aheterocyclicalkyl, an alkoxy, a haloalkoxy, an amino, an alkylamino, adialkylamino, an arylamino, a diarylamino, an alkylarylamino, analkoxyhaloalkyl, a haloalkoxy, a sulfonic acid, a sulfonic ester, analkylsulfonic acid, an arylsulfonic acid, an arylalkoxy, an alkylthio,an arylthio, a cycloalkylthio, a cycloalkenyl, a cyano, an aminoalkyl,an aminoaryl, an aryl, an arylalkyl, an alkylaryl, a carboxamido, aalkylcarboxamido, an arylcarboxamido, an amidyl, a carboxyl, acarbamoyl, an alkylcarboxylic acid, an arylcarboxylic acid, analkylcarbonyl, an arylcarbonyl, an ester, a carboxylic ester, analkylcarboxylic ester, an arylcarboxylic ester, a haloalkoxy, asulfonamido, an alkylsulfonamido, an arylsulfonamido, a sulfonic ester,a urea, a phosphoryl, a nitro, —T—Q, or (C(R_(e))(R_(f)))_(k)—T—Q, orR_(e) and R_(f) taken together with the carbons to which they areattached form a carbonyl, a methanthial, a heterocyclic ring, acycloalkyl group or a bridged cycloalkyl group;

k is an integer from 1 to 3;

T at each occurrence is independently a covalent bond, a carbonyl, anoxygen, —S(O)_(o)— or —N(R_(a))R_(i)—;

o is an integer from 0 to 2;

R_(a) is a lone pair of electrons, a hydrogen or an alkyl group;

R_(i) is a hydrogen, an alkyl, an aryl, an alkylcarboxylic acid, anarylcarboxylic acid, an alkylcarboxylic ester, an arylcarboxylic ester,an alkylcarboxamido, an arylcarboxamido, an alkylaryl, an alkylsulfinyl,an alkylsulfonyl, an arylsulfinyl, an arylsulfonyl, a sulfonamido, acarboxamido, a carboxylic ester, an amino alkyl, an amino aryl,—CH₂—C(T—Q)(R_(e))(R_(f)), or —(N₂O₂—)⁻.M⁺, wherein M⁺ is an organic orinorganic cation; with the proviso that when R_(i) is—CH₂—C(T—Q)(R_(e))(R_(f)) or —(N₂O₂)⁻.M⁺, or R_(e) or R_(f) are T—Q or(C(R_(e))(R_(f)))_(k)—T—Q, then the “—T—Q” subgroup can be a hydrogen,an alkyl, an alkoxy, an alkoxyalkyl, an aminoalkyl, a hydroxy, aheterocyclic ring or an aryl group; with the proviso that when the T in“—T—Q” is oxygen then Q is not —NO₂; and the compounds of Formula (I)must contain at least one nitrite, nitrate, thionitrite or thionitrategroup.

In a preferred embodiment of the present invention, the “—T—D₂” group inFormula (I) is not N′-(2-nitroxyethyl), N′-(3-nitroxypropyl),N′-(4-nitrobenzyl), N′-(2-(4-nitrophenyl)-2-nitroxyethyl) orN′-(1-methyl-2-(4-nitrophenyl)-2-nitroxyethyl).

In cases where R_(e) and R_(f) are a heterocyclic ring or taken togetherR_(e) and R_(f) are a heterocyclic ring, then R_(i) can be a substituenton any disubstituted nitrogen contained within the radical where R_(i)is as defined herein.

In cases where multiple designations of variables which reside insequence are chosen as a “covalent bond” or the integer chosen is 0, theintent is to denote a single covalent bond connecting one radical toanother. For example, E₀ would denote a covalent bond, while E₂ denotes(E—E) and (C(R_(e))(R_(f)))₂ denotes —C(R_(e))(R_(f))—C(R_(e))(R_(f))—,where R_(e) and R_(f) at each occurrence are each independently selectedfrom those moieties defined herein.

Another embodiment of the present invention describes novel nitrosatedand/or nitrosylated potassium channel activators of Formula (II):

wherein

R₃ is a hydrogen, an alkyl, an aryl, an alkylaryl or K;

D₃ is a hydrogen or D₂, with the proviso that at least one D₃ must bedesignated as D₂ if R₃ is not K;

G is:

R₄, R₅, and R₆ are each independently a hydrogen, a halogen, a hydroxy,a lower alkyl, an alkoxy, a nitrile, a nitrite, a carboxyamido, acarboxylic ester, an alkylsulfinyl, an arylsulfinyl, an aminoalkyl, analkylthio, or an arylthio; or R₅ and R₆ taken together are a group whichforms a ring with the two carbon atoms to which they are attached,wherein the group is —S(O)_(t)—(CH₂)_(r)—CH₂—, —C(O)Z—(CH₂)_(o)—CH₂, or—C(O)—CH₂—(CH₂)_(o)—Z—;

t is an integer of 1 or 2;

r is an integer from 1 to 3;

Z is oxygen, NR₇ or CH₂;

R₇ is hydrogen or R₃; and

o and D₂ are as defined herein.

Another embodiment of the present invention describes novel nitrosatedand/or nitrosylated potassium channel activators of Formula (III):

wherein

X—(CH₂)_(a)— or oxygen;

Y is:

R₇ and R₈ are each independently a hydrogen, an alkylcarbonyl, analkoxycarbonyl, a heterocyclic ring, an ester, a nitro, a cyano, a halo,a haloalkyl, an alkylsulphinyl, an alkylsulphonyl, a sulfonic ester, anamidyl, a carbamate, a formyl, a sulfonamido, or a carboxamido;

R₉ is an aryl or a heterocyclic ring;

R₁₀ is a carboxylic ester, a carboxylic acid, a carboxamido, a urea, athiourea, an amidyl, a sulfamoyl, a hydroxyalkyl, —C(O)OD,—N(R₅₉)(C═NCN)NR₅₁R₅₇, —N(R₅₉)(C═NCN)SR₁₂, —N(R₅₉)(C═NCN)OR₁₂,—P(O)(OR₅₀)₂, —P(O)(O(CH₂)_(k′)O), —SR₁₁, —S(O)R₁₁, —S(O)₂R₁₁, —OR₁₁, acyano, a heterocyclic ring, a pyridine N-oxide or—C(NR₅₁R₅₇)═CH—C(O)R₅₉;

R₁₁ is a hydrogen, an alkyl, an aryl, an arylalkyl, a cycloalkyl, orcycloalkylalkyl;

R₁₂ is an alkyl, an aryl, an alkylaryl, or an arylheterocyclic ring;

R₁₃ is aryl, a heterocyclic ring, a cycloalkyl

X₁ is an oxygen, a sulfur, or —NH—;

X₂ is a hydrogen or an alkyl group;

X₃ is oxygen or sulfur;

k′ is an interger from 2 to 4;

a′ and b′ are each independently an integer from 0 to 3; and

a, D, D₂,R₅₀,R₅₁,R₅₇ and R₅₉ are as defined herein.

Another embodiment of the present invention describes novel nitrosatedand/or nitrosylated potassium channel activators of Formula (IV):

wherein,

D₃ is hydrogen or D₂ with the proviso that at least one D₃ must be D₂;and

D₂ is as defined herein.

Another embodiment of the present invention describes novel nitrosatedand/or nitrosylated potassium channel activators of Formula (V):

wherein,

R₁₄ and R₁₅ are independently selected from a lower alkyl, a lowerhaloalkyl or R₁₄ and R₁₅ together with the carbon to which they areattached form a cyclic haloalkyl group;

A₁—B₁ is —NHC(O)—, —OCH₂—, —SCH₂—NHCH₂, —CH═CH—, or —CH═CH—; and

Y₁ is an aryl group; and

D₂ is as defined herein.

Another embodiment of the present invention describes novel nitrosatedand/or nitrosylated potassium channel activators of Formula (VI):

wherein,

R₁₆ and R₁₇ are each independently a lower alkyl, a lower haloalkyl orR₁₆ and R₁₇ together with the carbon to which they are attached form acyclic haloalkyl group;

Y₃ is an sp²-hybridized atom and Y₂, Y₃, and Y₄ together with the carbonatoms to which they are attached form a 5- or 6-membered heterocyclicring;

R₁₈ and R₁₉ are each independently a hydrogen, a nitro, a cyano, a halo,a haloalkyl, an alkylsulfonyl, or an aryl, with the proviso that eitherR₁₈ or R₁₉ must be a hydrogen but that both R₁₈ and R₁₉ cannot be ahydrogen; and

D₂ is as defined herein.

Compounds of the present invention which have one or more asymmetriccarbon atoms can exist as the optically pure enantiomers, purediastereomers, mixtures of enantiomers, mixtures of diastereomers,racemic mixtures of enantiomers, diastereomeric racemates or mixtures ofdiastereomeric racemates. It is to be understood that the presentinvention anticipates and includes within its scope all such isomers andmixtures thereof.

Another aspect of the present invention provides processes for makingthe novel compounds of the invention and to the intermediates useful insuch processes. The compounds of the present invention of Formula (I),Formula (II) Formula (III), Formula (IV), Formula (V) and Formula (III)can be synthesized by one skilled in the art following the methods andexamples described herein. Compounds of the invention can be synthesizedas shown in FIGS. 1-16 in which A, B, A₁, B₁, D, D₁, D₃, E, G, Q, T, W,X, R₁, R₂, R₃, R₄, R₅, R₆, R₇, R₈, R₁₄, R₁₅, R₁₆, R₁₇, R₁₈, R₁₉, R_(e),R_(f), a, b, c, d, g, i, j, p, q, x, y and z are as defined herein or asdepicted in the reaction schemes for Formulas (I), (II), (III), (IV),(V) and (VI); P¹ is an oxygen protecting group and P² is a sulfurprotecting group. The reactions are performed in solvents appropriate tothe reagents, and materials used are suitable for the transformationsbeing effected. It is understood by one skilled in the art of organicsynthesis that the functionality present in the molecule must beconsistent with the chemical transformation proposed. This will, onoccasion, necessitate judgment by the routineer as to the order ofsynthetic steps, protecting groups required, and deprotectionconditions. Substituents on the starting materials may be incompatiblewith some of the reaction conditions required in some of the methodsdescribed, but alternative methods and substituents compatible with thereaction conditions will be readily apparent to one skilled in the art.The use of sulfur and oxygen protecting groups is known in the art forprotecting thiol and alcohol groups against undesirable reactions duringa synthetic procedure and many such protecting groups are known, e.g.,T. H. Greene and P. G. M. Wuts, Protective Groups in Organic Synthesis,John Wiley & Sons, New York (1991).

Nitroso compounds of Formula (I) where R₁ is as defined herein and anitrite containing N-amide is representative of the (C(B)—T—D) group asdefined herein can be prepared as outlined in FIG. 1. The acid group ofstructure 1 is converted to the amide of structure 2 wherein R is—W_(a−)—E_(b)—(C(R_(e))(R_(f)))_(p)—E_(c)—(C(R_(e))(R_(f)))_(x)—W_(d)—(C(R_(e))(R_(f)))_(y)—W_(i)—E_(j)—W_(g)—(C(R_(e))(R_(f)))_(z)by reaction with an appropriate protected alcohol containing amine,wherein R_(i) and P¹ are as defined herein. Preferred methods for thepreparation of amides are initially forming the mixed anhydride viareaction of the acid with a chloroformate, such asisobutylchloroformate, in the presence of a non-nucleophilic base, suchas triethylamine, in an anhydrous inert solvent, such asdichloromethane, diethylether or THF. The mixed anhydride is thenreacted with the monoprotected alcohol, preferably in the presence of acondensation catalyst, such as 4-dimethylamino pyridine (DMPA).Alternatively, the acid can first be converted to the acid chloride bytreatment with oxalyl chloride in the presence of a catalytic amount ofDMF. The acid chloride is then reacted with the protected alcoholcontaining amine, preferably in the presence of a condensation catalyst,such as 4-dimethylamino pyridine (DMAP), and a tertiary amine base, suchas triethyl amine, to produce the amide. Alternatively, the acid andprotected alcohol containing amine can be coupled to produce the amideby treatment with a dehydration agent, such as dicyclohexylcarbodiimide(DCC) or 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride(EDC) with or without a condensation catalyst such as DMAP. Preferredprotecting groups for the alcohol moiety are silyl ethers, such as atrimethylsilyl or a tert-butyldimethylsilyl ether. Deprotection of thehydroxyl moiety (fluoride ion is the preferred method for removing silylether protecting groups) followed by reaction with a suitablenitrosylating agent, such as thionyl chloride nitrite, thionyl dinitriteor nitrosium tetrafluoroborate, in a suitable anhydrous solvent, such asdichlormethane, THF, DMF or acetonitrile, with or without an amine base,such as pyridine or triethylamine, produces the compounds of structureIA.

Nitroso compounds of Formula (I) wherein R₁ is as defined herein and anitrosothiol containing amide is representative of the (C(B)—T—D) groupas defined herein can be prepared as outlined in FIG. 2. The acid groupof structure 1 is converted to the amide of structure 3 by reaction withan appropriate protected thiol containing amine wherein R, R_(i) and P²are as defined herein. Preferred methods for the preparation of amidesare initially forming the mixed anhydride via reaction of the acid witha chloroformate, such as isobutylchloroformate, in the presence of anon-nucleophilic base, such as triethylamine, in an anhydrous inertsolvent, such as dichloromethane, diethylether or THF. The mixedanhydride is then reacted with the thiol protected amine, preferably inthe presence of a condensation catalyst, such as 4-dimethylaminopyridine (DMAP). Alternatively, the acid can first be converted to theacid chloride by treatment with oxalyl chloride in the presence of acatalytic amount of DMF. The acid chloride is then reacted with theprotected thiol containing amine, preferably in the presence of acondensation catalyst, such as 4-dimethylamino pyridine (DMAP), and atertiary amine base, such as triethyl amine, to produce the amide.Alternatively, the acid and protected thiol containing amine can becoupled to produce the amide by treatment with a dehydration agent, suchas dicyclohexyl-carbodiimide (DCC) or1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC) withor without a condensation catalyst such as DMAP. Preferred protectinggroups for the thiol moiety are as a thioester, such as thioacetate orthiobenzoate, as a disulfide, as a thiocarbamate, such asN-methoxymethyl thiocarbamate, or as a thioether, such asparamethoxybenzyl thioether, a 2,4,6-trimethoxybenzyl thioether, atetrahydropyranyl thioether, or a S-triphenylmethyl thioether.Deprotection of the thiol moiety (zinc in dilute aqueous acid,triphenylphosphine in water and sodium borohydride are preferred methodsfor reducing disulfide groups while aqueous base is typically used tohydrolyze thioesters and N-methoxymethyl thiocarbamates and mercurictrifluoroacetate, silver nitrate or strong acids such as trifluoroaceticor hydrochloric acid and heat are used to remove a paramethoxybenzylthioether, a 2,4,6-trimethoxybenzyl thioether a tetrahydropyranylthioether or a S-triphenylmethyl thioether group) followed by reactionwith a suitable nitrosylating agent, such as thionyl chloride nitrite,thionyl dinitrite, a lower alkyl nitrite, such as tert-butyl nitrite, ornitrosium tetrafluoroborate, in a suitable anhydrous solvent, such asmethylene chloride, THF, DMF or acetonitrile, with or without an aminebase, such as pyridine or triethylamine, produces the compounds ofstructure IB. Alternatively, a stoichiometric quantity of sodium nitritein alcoholic or aqueous acid produces the compounds of structure IB.

Nitroso compounds of Formula (I) wherein R₁ is as defined herein and anitrite containing N-cyano-N′substituted-carboximidamide isrepresentative of the (C(B)—T—D) group as defined herein can be preparedas outlined in FIG. 3. The imidate of structure 4 wherein R′ is an alkylor cycloalkyl group is converted to the N-cyano-carboximidate ofstructure 5 by reaction with cyanamide in buffered solution between pH5.0-6.0. The compound of structure 5 is converted to the compound ofstructure 6 by reaction with an appropriate protected alcohol containingamine wherein R, R_(i) and P¹ are as defined herein in an appropriatesolvent such as methanol, ethanol, methylene chloride, THF, chloroform,dioxane or carbon tetra-chloride. Preferred protecting groups for thealcohol moiety are silyl ethers, such as a trimethylsilyl or atert-butyldimethylsilyl ether. Deprotection of the hydroxyl moiety(fluoride ion is the preferred method for removing silyl etherprotecting groups) followed by reaction with a suitable nitrosylatingagent, such as thionyl chloride nitrite, thionyl dinitrite or nitrosiumtetrafluoroborate, in a suitable anhydrous solvent, such asdichlormethane, THF, DMF or acetonitrile, with or without an amine base,such as pyridine or triethylamine, produces the compounds of structureIC.

Nitroso compounds of Formula (I) wherein R₁ is as defined herein and anitrosothiol containing N-cyano-N′substituted-carboximidamide isrepresentative of the (C(B)—T—D) group as defined herein can be preparedas outlined in FIG. 4. The compound of structure 5 wherein R′ is asdefined herein is converted to the compound of structure 7 by reactionwith an appropriate protected thiol containing amine wherein R, R_(i)and P² are as defined herein in an appropriate solvent such as methanol,ethanol, methylene chloride, THF, chloroform, dioxane or carbontetra-chloride. Preferred protecting groups for the thiol moiety are asa disulfide, as a thiocarbamate, such as N-methoxymethyl thiocarbamate,or as a thioether, such as paramethoxybenzyl thioether, a2,4,6-trimethoxybenzyl thioether, a tetrahydropyranyl thioether, or aS-triphenylmethyl thioether. Deprotection of the thiol moiety (zinc indilute aqueous acid, triphenylphosphine in water and sodium borohydrideare preferred methods for reducing disulfide groups while mercurictrifluoroacetate, silver nitrate or strong acids such as trifluoroaceticor hydrochloric acid and heat are used to remove a paramethoxybenzylthioether, a 2,4,6-trimethoxybenzyl thioether a tetrahydropyranylthioether or a S-triphenylmethyl thioether group) followed by reactionwith a suitable nitrosylating agent, such as thionyl chloride nitrite,thionyl dinitrite, a lower alkyl nitrite, such as tert-butyl nitrite, ornitrosium tetrafluoroborate, in a suitable anhydrous solvent, such asmethylene chloride, THF, DMF or acetonitrile, with or without an aminebase, such as pyridine or triethylamine, produces the compounds ofstructure ID. Alternatively, a stoichiometric quantity of sodium nitritein alcoholic or aqueous acid produces the compounds of structure ID.

Nitroso compounds of Formula (I) wherein R₁ is as defined herein and anitrite containing N-cyano-N′substituted-carboximidamide isrepresentative of the (C(B)—T—D) group as defined herein can be preparedas outlined in FIG. 5. The amide of formula 2 wherein R, R_(i) and P¹are as defined herein is converted to the compound of structure 8 byreaction with P₂S₅ or Lawesson's reagent under standard conditions (cf.Tetrahedron, 35, 2433 (1979)). The compound of structure 8 is convertedto the compound of structure 6 by reaction with excess cyanamide in thepresence. of phosphorus oxychloride, phosphorus pentoxide, phosphoruspentachloride, thionyl chloride, or sulfuryl chloride in the presence ofa tertiary amine such as triethylamine or diisopropylethyl amine in aninert solvent such as acetonitrile, benzene, toluene, methylenechloride, chloroform, carbon tetrachloride, tetrahydrofuran, DMF and thelike at a temperature ranging from room temperature up to theatmospheric boiling temperature of the solvent. The compound ofstructure 6 is converted into the compound of structure IC as describedherein.

Nitroso compounds of Formula (I) wherein R₁ is as defined herein and anitrite containing N-cyano-N′substituted-carboximidamide isrepresentative of the (C(B)—T—D) group as defined herein can be preparedas outlined in FIG. 6. The amide of structure 3 wherein R, R_(i) and P²are as defined herein is converted to the compound of structure 9 byreaction with P₂S₅ or Lawesson's reagent as described herein. Thecompound of structure 9 is converted to the compound of structure 7 byreaction with excess cyanamide in the presence of phosphorusoxychloride, phosphorus pentoxide, phosphorus pentachloride, thionylchloride, or sulfuryl chloride in the presence of a tertiary amine suchas triethylamine or diisopropylethyl amine in an inert solvent such asacetonitrile, benzene, toluene, methylene chloride, chloroform, carbontetrachloride, tetrahydrofuran, DMF and the like at a temperatureranging from room temperature up to the atmospheric boiling temperatureof the solvent. The compound of structure 7 is converted into thecompound of structure ID as described herein.

Nitroso compounds of Formula (II) wherein G and R₃ are as defined hereinand a nitrite containing acyl group is representative of the D₃ group asdefined herein can be prepared as outlined in FIG. 7. The substitutedcyano guanidine of structure 10 is converted to the compound of thestructure 11 wherein R is as defined herein by reaction with anappropriate protected alcohol containing activated acylating agentwherein P¹ is as defined herein. Preferred methods for the formation ofacylated substituted cyanoguanidines is reacting the substitutedcyanoguanidine with the preformed acid chloride or symmetrical anhydrideof the protected alcohol containing acid or condensing the substitutedcyanoguanidine and protected alcohol containing acid in the presence ofa dehydrating agent such as dicyclohexylcarbo-diimide (DCC) or1-ethyl-3(3-dimethylaminopropyl)carbodiimide hydrochloride (EDAC.HCl)with a catalyst such as 4-dimethylaminopyridine (DMAP) or1-hydroxy-benzotriazole (HOBt). Preferred protecting groups for thealcohol moiety are silyl ethers such as a trimethylsilyl ortert-butyldimethylsilyl ether. Deprotection of the hydroxyl moiety(fluoride ion is the preferred method for removing silyl etherprotecting groups) followed by reaction a suitable nitrosylating agentsuch as thionyl chloride nitrite, thionyl dinitrite, or nitrosoniumtetrafluoroborate in a suitable anhydrous solvent such asdichloromethane, THF, DMF, or acetonitrile with or without an amine basesuch as pyridine or triethylamine affords the compound of the structureIIA.

Nitroso compounds of Formula (II) wherein G and R₃ are as defined hereinand a nitrosothiol containing acyl group is representative of the D₃group as defined herein can be prepared as outlined in FIG. 8. Thesubstituted cyano guanidine of structure 10 is converted to the compoundof the structure 12 wherein R is as defined herein by reaction with anappropriate protected thiol containing activated acylating agent whereinP² is as defined herein. Preferred methods for the formation of acylatedsubstituted cyanoguanidines are reacting the substituted cyanoguanidinewith the preformed acid chloride or symmetrical anhydride of theprotected thiol containing acid or condensing the substitutedcyanoguanidine and protected thiol containing acid in the presence of adehydrating agent such as dicyclohexylcarbodiimide (DCC) or1-ethyl-3(3-dimethylaminopropyl)carbodiimide hydrochloride (EDAC.HCl)with a catalyst such as 4-dimethylaminopyridine (DMAP) or1-hydroxybenzotriazole (HOBt). Preferred protecting groups for the thiolmoiety are as a thioester, such as thioacetate or thiobenzoate, as adisulfide, as a thiocarbamate, such as N-methoxy-methyl thiocarbamate,or as a thioether, such as paramethoxybenzyl thioether, a2,4,6-trimethoxybenzyl thioether, a tetrahydropyranyl thioether, or aS-triphenylmethyl thioether. Deprotection of the thiol moiety (zinc indilute aqueous acid, triphenyl-phosphine in water and sodium borohydrideare preferred methods for reducing disulfide groups while aqueous baseis typically used to hydrolyze thioesters and N-methoxymethylthiocarbamates and mercuric trifluoroacetate, silver nitrate or strongacids such as trifluoroacetic or hydrochloric acid and heat are used toremove a paramethoxybenzyl thioether, a 2,4,6-trimethoxybenzyl thioethera tetrahydropyranyl thioether or a S-triphenylmethyl thioether group)followed by reaction with a suitable nitrosylating agent, such asthionyl chloride nitrite, thionyl dinitrite, a lower alkyl nitrite, suchas tert-butyl nitrite, or nitrosium tetrafluoroborate, in a suitableanhydrous solvent, such as methylene chloride, THF, DMF or acetonitrile,with or without an amine base, such as pyridine or triethylamine,produces the compounds of structure IIB. Alternatively, a stoichiometricquantity of sodium nitrite in alcoholic or aqueous acid produces thecompounds of structure IIB.

Nitroso compounds of Formula (III) wherein X, Y, R₇ and R₈ are definedas herein and a nitrite containing acyl group is representative of theD₂ group as defined herein can be prepared as outlined in FIG. 9. Thealcohol of structure 13 is converted to the acyl derivative of thestructure 14 wherein R is as defined herein by reaction with anappropriate protected alcohol containing activated acylating agentwherein P¹ is as defined herein. Preferred methods for the formation ofesters is reacting the alcohol with the preformed acid chloride orsymmetrical anhydride of the protected alcohol containing acid orcondensing the alcohol and protected alcohol containing acid in thepresence of a dehydrating agent such as dicyclohexylcarbodiimide (DCC)or 1-ethyl-3(3-dimethyl-aminopropyl)carbodiimide hydrochloride(EDAC.HCl) with a catalyst such as 4-dimethylaminopyridine (DMAP) or1-hydroxybenzotriazole (HOBt). Preferred protecting groups for thealcohol moiety are silyl ethers such as a trimethylsilyl ortert-butyldimethylsilyl ether. Deprotection of the hydroxyl moiety(fluoride ion is the preferred method for removing silyl etherprotecting groups) followed by reaction a suitable nitrosylating agentsuch as thionyl chloride nitrite, thionyl dinitrite, or nitrosoniumtetrafluoroborate in a suitable anhydrous solvent such asdichloro-methane, THF, DMF, or acetonitrile with or without an aminebase such as pyridine or triethylamine affords the compound of thestructure IIIA.

Nitroso compounds of Formula (III) wherein X, Y, R₇ and R₈ are definedas herein and a nitrosothiol containing acyl group is representative ofthe D₂ group as defined herein can be prepared as outlined in FIG. 10.The alcohol of structure 13 is converted to the acyl derivative of thestructure 15 wherein R is as defined herein by reaction with anappropriate protected thiol containing activated acylating agent whereinP² is as defined herein. Preferred methods for the formation of estersare reacting the alcohol with the preformed acid chloride or symmetricalanhydride of the protected thiol containing acid or condensing thealcohol and protected thiol containing acid in the presence of adehydrating agent such as dicyclohexylcarbodiimide (DCC) or1-ethyl-3(3-dimethyl-aminopropyl)carbodiimide hydrochloride (EDAC.HCl)with a catalyst such as 4-dimethylaminopyridine (DMAP) or1-hydroxybenzotriazole (HOBt). Preferred protecting groups for the thiolmoiety are as a thioester, such as thioacetate or thiobenzoate, as adisulfide, as a thiocarbamate, such as N-methoxymethyl thiocarbamate, oras a thioether, such as paramethoxybenzyl thioether, a2,4,6-trimethoxybenzyl thioether, a tetrahydropyranyl thioether, or aS-triphenylmethyl thioether. Deprotection of the thiol moiety (zinc indilute aqueous acid, triphenylphosphine in water and sodium borohydrideare preferred methods for reducing disulfide groups while aqueous baseis typically used to hydrolyze thioesters and N-methoxymethylthiocarbamates and mercuric trifluoroacetate, silver nitrate or strongacids such as trifluoroacetic or hydrochloric acid and heat are used toremove a paramethoxybenzyl thioether, a 2,4,6-trimethoxybenzyl thioethera tetrahydropyranyl thioether or a S-triphenylmethyl thioether group)followed by reaction with a suitable nitrosylating agent, such asthionyl chloride nitrite, thionyl dinitrite, a lower alkyl nitrite, suchas tert-butyl nitrite, or nitrosium tetrafluoroborate, in a suitableanhydrous solvent, such as methylene chloride, THF, DMF or acetonitrile,with or without an amine base, such as pyridine or triethylamine,produces the compounds of structure IIIB. Alternatively, astoichiometric quantity of sodium nitrite in alcoholic or aqueous acidproduces the compounds of structure IIIB.

Nitroso compounds of Formula (IV) wherein a nitrite containing acylgroup is representative of the D₃ group as defined herein can beprepared as outlined in FIG. 11. The amine of structure 16 is convertedto the acyl derivative of the structure 17 wherein R is as definedherein by reaction with an appropriate protected alcohol containingactivated acylating agent wherein P¹ is as defined herein. Preferredmethods for the formation of amides is reacting the amine with thepreformed acid chloride or symmetrical anhydride of the protectedalcohol containing acid or condensing the alcohol and protected alcoholcontaining acid in the presence of a dehydrating agent such asdicyclohexylcarbodiimide (DCC) or1-ethyl-3(3-dimethyl-aminopropyl)carbodiimide hydrochloride (EDAC.HCl)with a catalyst such as 4-dimethylaminopyridine (DMAP) or1-hydroxybenzotriazole (HOBt). Preferred protecting groups for thealcohol moiety are silyl ethers such as a trimethylsilyl ortert-butyldimethylsilyl ether. Deprotection of the hydroxyl moiety(fluoride ion is the preferred method for removing silyl etherprotecting groups) followed by reaction a suitable nitrosylating agentsuch as thionyl chloride nitrite, thionyl dinitrite, or nitrosoniumtetrafluoroborate in a suitable anhydrous solvent such asdichloro-methane, THF, DMF, or acetonitrile with or without an aminebase such as pyridine or triethylamine affords the compound of thestructure IVA.

Nitroso compounds of Formula (IV) where a nitrosothiol containing acylgroup is representative of the D₃ group as defined herein can beprepared as outlined in FIG. 12. The amine of structure 16 is convertedto the acyl derivative of the structure 18 wherein R is as definedherein by reaction with an appropriate protected thiol containingactivated acylating agent wherein P² is as defined herein. Preferredmethods for the formation of amides are reacting the alcohol with thepreformed acid chloride or symmetrical anhydride of the protected thiolcontaining acid or condensing the alcohol and protected thiol containingacid in the presence of a dehydrating agent such asdicyclohexylcarbodiimide (DCC) or1-ethyl-3(3-dimethyl-aminopropyl)carbodiimide hydrochloride (EDAC.HCl)with a catalyst such as 4-dimethylaminopyridine (DMAP) or1-hydroxybenzotriazole (HOBt). Preferred protecting groups for the thiolmoiety are as a thioester, such as thioacetate or thiobenzoate, as adisulfide, as a thiocarbamate, such as N-methoxymethyl thiocarbamate, oras a thioether, such as paramethoxybenzyl thioether, a2,4,6-trimethoxybenzyl thioether, a tetrahydropyranyl thioether, or aS-triphenylmethyl thioether. Deprotection of the thiol moiety (zinc indilute aqueous acid, triphenylphosphine in water and sodium borohydrideare preferred methods for reducing disulfide groups while aqueous baseis typically used to hydrolyze thioesters and N-methoxymethylthiocarbamates and mercuric trifluoroacetate, silver nitrate or strongacids such as trifluoroacetic or hydrochloric acid and heat are used toremove a paramethoxybenzyl thioether, a 2,4,6-trimethoxybenzyl thioethera tetrahydropyranyl thioether or a S-triphenylmethyl thioether group)followed by reaction with a suitable nitrosylating agent, such asthionyl chloride nitrite, thionyl dinitrite, a lower alkyl nitrite, suchas tert-butyl nitrite, or nitrosium tetrafluoroborate, in a suitableanhydrous solvent, such as methylene chloride, THF, DMF or acetonitrile,with or without an amine base, such as pyridine or triethylamine,produces the compounds of structure IVB. Alternatively, a stoichiometricquantity of sodium nitrite in alcoholic or aqueous acid produces thecompounds of structure IVB.

Nitroso compounds of Formula (V) wherein A₁, B₁, Y₁, R₁₄ and R₁₅ aredefined as herein and a nitrite containing acyl group is representativeof the D₂ group as defined herein can be prepared as outlined in FIG.13. The alcohol of structure 19 is converted to the acyl derivative ofthe structure 20 wherein R is as defined herein by reaction with anappropriate protected alcohol containing activated acylating agentwherein P¹ is as defined herein. Preferred methods for the formation ofesters is reacting the alcohol with the preformed acid chloride orsymmetrical anhydride of the protected alcohol containing acid orcondensing the alcohol and protected alcohol containing acid in thepresence of a dehydrating agent such as dicyclohexylcarbodiimide (DCC)or 1-ethyl-3(3-dimethyl-aminopropyl)carbodiimide hydrochloride(EDAC.HCl) with a catalyst such as 4-dimethylaminopyridine (DMAP) or1-hydroxybenzotriazole (HOBt). Preferred protecting groups for thealcohol moiety are silyl ethers such as a trimethylsilyl ortert-butyldimethylsilyl ether. Deprotection of the hydroxyl moiety(fluoride ion is the preferred method for removing silyl etherprotecting groups) followed by reaction a suitable nitrosylating agentsuch as thionyl chloride nitrite, thionyl dinitrite, or nitrosoniumtetrafluoroborate in a suitable anhydrous solvent such asdichloro-methane, THF, DMF, or acetonitrile with or without an aminebase such as pyridine or triethylamine affords the compound of thestructure VA.

Nitroso compounds of Formula (V) wherein A, B, Y₁, R₁₄ and R₁₅ aredefined as herein and a nitrosothiol containing acyl group isrepresentative of the D₂ group as defined herein can be prepared asoutlined in FIG. 14. The alcohol of structure 19 is converted to theacyl derivative of the structure 21 wherein R is as defined herein byreaction with an appropriate protected thiol containing activatedacylating agent wherein P² is as defined herein. Preferred methods forthe formation of esters are reacting the alcohol with the preformed acidchloride or symmetrical anhydride of the protected thiol containing acidor condensing the alcohol and protected thiol containing acid in thepresence of a dehydrating agent such as dicyclohexylcarbodiimide (DCC)or 1-ethyl-3(3-dimethyl-aminopropyl)carbodiimide hydrochloride(EDAC.HCl) with a catalyst such as 4-dimethylaminopyridine (DMAP) or1-hydroxybenzotriazole (HOBt). Preferred protecting groups for the thiolmoiety are as a thioester, such as thioacetate or thiobenzoate, as adisulfide, as a thiocarbamate, such as N-methoxymethyl thiocarbamate, oras a thioether, such as paramethoxybenzyl thioether, a2,4,6-trimethoxybenzyl thioether, a tetrahydropyranyl thioether, or aS-triphenylmethyl thioether. Deprotection of the thiol moiety (zinc indilute aqueous acid, triphenylphosphine in water and sodium borohydrideare preferred methods for reducing disulfide groups while aqueous baseis typically used to hydrolyze thioesters and N-methoxymethylthiocarbamates and mercuric trifluoroacetate, silver nitrate or strongacids such as trifluoroacetic or hydrochloric acid and heat are used toremove a paramethoxybenzyl thioether, a 2,4,6-trimethoxybenzyl thioethera tetrahydropyranyl thioether or a S-triphenylmethyl thioether group)followed by reaction with a suitable nitrosylating agent, such asthionyl chloride nitrite, thionyl dinitrite, a lower alkyl nitrite, suchas tert-butyl nitrite, or nitrosium tetrafluoroborate, in a suitableanhydrous solvent, such as methylene chloride, THF, DMF or acetonitrile,with or without an amine base, such as pyridine or triethylamine,produces the compounds of structure VB. Alternatively, a stoichiometricquantity of sodium nitrite in alcoholic or aqueous acid produces thecompounds of structure VB.

Nitroso compounds of Formula (VI) wherein Y₂, Y₃, Y₄, R₁₄, R₁₅, R₁₆ andR₁₇ are defined as herein and a nitrite containing acyl group isrepresentative of the D₂ group as defined herein can be prepared asoutlined in FIG. 15. The alcohol of structure 22 is converted to theacyl derivative of the structure 23 wherein R is as defined herein byreaction with an appropriate protected alcohol containing activatedacylating agent wherein P¹ is as defined herein. Preferred methods forthe formation of esters is reacting the alcohol with the preformed acidchloride orsymmetrical anhydride of the protected alcohol containingacid or condensing the alcohol and protected alcohol containing acid inthe presence of a dehydrating agent such as dicyclohexylcarbodiimide(DCC) or 1-ethyl-3(3-dimethyl-aminopropyl)carbodiimide hydrochloride(EDAC.HCl) with a catalyst such as 4-dimethylaminopyridine (DMAP) or1-hydroxybenzotriazole (HOBt). Preferred protecting groups for thealcohol moiety are silyl ethers such as a trimethylsilyl ortert-butyldimethylsilyl ether. Deprotection of the hydroxyl moiety(fluoride ion is the preferred method for removing silyl etherprotecting groups) followed by reaction a suitable nitrosylating agentsuch as thionyl chloride nitrite, thionyl dinitrite, or nitrosoniumtetrafluoroborate in a suitable anhydrous solvent such asdichloro-methane, THF, DMF, or acetonitrile with or without an aminebase such as pyridine or triethylamine affords the compound of thestructure VIA.

Nitroso compounds of Formula (VI) wherein Y₂, Y₃, Y₄, R₁₄, R₁₅, R₁₆ andR₁₇ are defined as herein and a nitrosothiol containing acyl group isrepresentative of the D₂ group as defined herein can be prepared asoutlined in FIG. 16. The alcohol of structure 22 is converted to theacyl derivative of the structure 24 wherein R is as defined herein byreaction with an appropriate protected thiol containing activatedacylating agent wherein P² is as defined herein. Preferred methods forthe formation of esters are reacting the alcohol with the preformed acidchloride or symmetrical anhydride of the protected thiol containing acidor condensing the alcohol and protected thiol containing acid in thepresence of a dehydrating agent such as dicyclohexylcarbodiimide (DCC)or 1-ethyl-3(3-dimethyl-aminopropyl)carbodiimide hydrochloride(EDAC.HCl) with a catalyst such as 4-dimethylaminopyridine (DMAP) or1-hydroxybenzotriazole (HOBt). Preferred protecting groups for the thiolmoiety are as a thioester, such as thioacetate or thiobenzoate, as adisulfide, as a thiocarbamate, such as N-methoxymethyl thiocarbamate, oras a thioether, such as paramethoxybenzyl thioether, a2,4,6-trimethoxybenzyl thioether, a tetrahydropyranyl thioether, or aS-triphenylmethyl thioether. Deprotection of the thiol moiety (zinc indilute aqueous acid, triphenylphosphine in water and sodium borohydrideare preferred methods for reducing disulfide groups while aqueous baseis typically used to hydrolyze thioesters and N-methoxymethylthiocarbamates and mercuric trifluoroacetate, silver nitrate or strongacids such as trifluoroacetic or hydrochloric acid and heat are used toremove a paramethoxybenzyl thioether, a 2,4,6-trimethoxybenzyl thioethera tetrahydropyranyl thioether or a S-triphenylmethyl thioether group)followed by reaction with a suitable nitrosylating agent, such asthionyl chloride nitrite, thionyl dinitrite, a lower alkyl nitrite, suchas tert-butyl nitrite, or nitrosium tetrafluoroborate, in a suitableanhydrous solvent, such as methylene chloride, THF, DMF or acetonitrile,with or without an amine base, such as pyridine or triethylamine,produces the compounds of structure VIB. Alternatively, a stoichiometricquantity of sodium nitrite in alcoholic or aqueous acid produces thecompounds of structure VIB.

The compounds. of the present invention include potassium channelactivators, including those described herein, which have been nitrosatedand/or nitrosylated through one or more sites such as oxygen (hydroxylcondensation), sulfur (sulfhydryl condensation), carbon and/or nitrogen.The nitrosated and/or nitrosylated potassium channel activators of thepresent invention donate, transfer or release a biologically active formof nitrogen monoxide (nitric oxide).

Nitrogen monoxide can exist in three forms: NO− (nitroxyl), NO.(nitricoxide) and NO⁺ (nitrosonium). NO. is a highly reactive short-livedspecies that is potentially toxic to cells. This is critical because thepharmacological efficacy of NO depends upon the form in which it isdelivered. In contrast to the nitric oxide radical (NO.), nitrosonium(NO+) does not react with O₂ or o₂-species, and functionalities capableof transferring and/or releasing NO⁺ and NO− are also resistant todecomposition in the presence of many redox metals. Consequently,administration of charged NO equivalents (positive and/or negative) doesnot result in the generation of toxic by-products or the elimination ofthe active NO moiety.

Compounds contemplated for use in the present invention (e.g., potassiumchannel activators and/or nitrosated and/or nitrosylated potassiumchannel activators) are, optionally, used in combination with nitricoxide and compounds that release nitric oxide or otherwise directly orindirectly deliver or transfer nitric oxide to a site of its activity,such as on a cell membrane in vivo.

The term “nitric oxide” encompasses uncharged nitric oxide (NO.) andcharged nitrogen monoxide species, preferably charged nitrogen monoxidespecies, such as nitrosonium ion (NO⁺) and nitroxyl ion (NO−). Thereactive form of nitric oxide can be provided by gaseous nitric oxide.The nitric oxide releasing, delivering or transferring compounds, havethe structure F—NO, wherein F is a nitric oxide releasing, delivering ortransferring moiety, include any and all such compounds which providenitric oxide to its intended site of action in a form active for itsintended purpose. The term “NO adducts” encompasses any nitrogenmonoxide releasing, delivering or transferring compounds, including, forexample, S-nitrosothiols, nitrites, nitrates, S-nitrothiols,sydnonimines, 2-hydroxy-2-nitrosohydrazines (NONOates),(E)-alkyl-2-[(E)-hydroxyimino]-5-nitro-3-hexene amines or amides,nitrosoamines, furoxans as well as substrates for the endogenous enzymeswhich synthesize nitric oxide. The “NO adducts” can bemono-nitrosylated, poly-nitrosylated, mono-nitrosated and/orpoly-nitrosated or a combination thereof at a variety of naturallysusceptible or artificially provided binding sites for biologicallyactive forms of nitrogen monoxide.

One group of NO adducts is the S-nitrosothiols, which are compounds thatinclude at least one —S—NO group. These compounds includeS-nitroso-polypeptides (the term “polypeptide” includes proteins andpolyamino acids that do not possess an ascertained biological function,and derivatives thereof); S-nitrosylated amino acids (including naturaland synthetic amino acids and their stereoisomers and racemic mixturesand derivatives thereof); S-nitrosylated sugars; S-nitrosylated,modified and unmodified, oligonucleotides (preferably of at least 5, andmore preferably 5-200 nucleotides); straight or branched, saturated orunsaturated, aliphatic or aromatic, substituted or unsubstitutedS-nitrosylated hydrocarbons; and S-nitroso heterocyclic compounds.S-nitrosothiols and methods for preparing them are described in U.S.Pat. Nos. 5,380,758 and 5,703,073; WO 97/27749; WO 98/19672; and Oae etal, Org. Prep. Proc. Int., 15(3):165-198 (1983), the disclosures of eachof which are incorporated by reference herein in their entirety.

Another embodiment of the present invention is S-nitroso amino acidswhere the nitroso group is linked to a sulfur group of asulfur-containing amino acid or derivative thereof. Such compoundsinclude, for example, S-nitroso-N-acetylcysteine, S-nitroso-captopril,S-nitroso-N-acetylpenicillamine, S-nitroso-homocysteine,S-nitroso-cysteine and S-nitroso-glutathione.

Suitable S-nitrosylated proteins include thiol-containing proteins(where the NO group is attached to one or more sulfur groups on an aminoacid or amino acid derivative thereof) from various functional classesincluding enzymes, such as tissue-type plasminogen activator (TPA) andcathepsin B; transport proteins, such as lipoproteins; heme proteins,such as hemoglobin and serum albumin; and biologically protectiveproteins, such as immunoglobulins, antibodies and cytokines. Suchnitrosylated proteins are described in WO 93/09806, the disclosure ofwhich is incorporated by reference herein in its entirety. Examplesinclude polynitrosylated albumin where one or more thiol or othernucleophilic centers in the protein are modified.

Other examples of suitable S-nitrosothiols include:

(i) HS(C(R_(e))(R_(f)))_(m)SNO;

(ii) ONS(C(R_(e))(R_(f)))_(m)R_(e); and

(iii) H₂N—CH(CO₂H)—(CH₂)_(m)—C(O)NH—CH(CH₂SNO)—C(O)NH—CH₂—CO₂H;

wherein m is an integer from 2 to 20; R_(e) and R_(f) are eachindependently a hydrogen, an alkyl, a cycloalkoxy, a halogen, a hydroxy,an hydroxyalkyl, an alkoxyalkyl, an arylheterocyclic ring, an alkylaryl,a cycloalkylalkyl, a heterocyclicalkyl, an alkoxy, a haloalkoxy, anamino, an alkylamino, a dialkylamino, an arylamino, a diarylamino, analkylarylamino, an alkoxyhaloalkyl, a haloalkoxy, a sulfonic acid, asulfonic ester, an alkylsulfonic acid, an arylsulfonic acid, anarylalkoxy, an alkylthio, an arylthio, a cycloalkylthio, a cycloalkenyl,a cyano, an aminoalkyl, an aminoaryl, an aryl, an arylalkyl, analkylaryl, a carboxamido, a alkylcarboxamido, an arylcarboxamido, anamidyl, a carboxyl, a carbamoyl, a carbamate, an alkylcarboxylic acid,an arylcarboxylic acid, an alkylcarbonyl, an arylcarbonyl, an ester, acarboxylic ester, an alkylcarboxylic ester, an arylcarboxylic ester, ahaloalkoxy, a sulfonamido, an alkylsulfonamido, an arylsulfonamido, asulfonic ester, a urea, a phosphoryl, a nitro, —T—Q, or(C(R_(e))(R_(f)))_(k)—T—Q, or R_(e) and R_(f) taken together with thecarbons to which they are attached form a carbonyl, a methanthial, aheterocyclic ring, a cycloalkyl group or a bridged cycloalkyl group; Qis —NO or —NO₂; and T is independently a covalent bond, a carbonyl, anoxygen, —S(O)_(o)— or —N(R_(a))R_(i)—, wherein o is an integer from 0 to2, R_(a) is a lone pair of electrons, a hydrogen or an alkyl group;R_(i) is a hydrogen, an alkyl, an aryl, an alkylcarboxylic acid, an arylcarboxylic acid, an alkylcarboxylic ester, an arylcarboxylic ester, analkylcarboxamido, an arylcarboxamido, an alkylaryl, an alkylsulfinyl, analkylsulfonyl, an arylsulfinyl, an arylsulfonyl, a sulfonamido, acarboxamido, a carboxylic ester, an amino alkyl, an amino aryl,—CH₂—C(T—Q)(R_(e))(R_(f)), or —(N₂O₂—)⁻.M⁺, wherein M⁺ is an organic orinorganic cation; with the proviso that when R_(i) is—CH₂—C(T—Q)(R_(e))(R_(f)) or —(N₂O₂—).M⁺; then “—T—Q” can be a hydrogen,an alkyl group, an alkoxyalkyl group, an aminoalkyl group, a hydroxygroup or an aryl group.

In cases where R_(e) and R_(f) are a heterocyclic ring or R_(e) andR_(f) when taken together with the carbon atoms to which they areattached are a heterocyclic ring, then R_(i) can be a substituent on anydisubstituted nitrogen contained within the radical wherein R_(i) is asdefined herein.

Nitrosothiols can be prepared by various methods of synthesis. Ingeneral, the thiol precursor is prepared first, then converted to theS-nitrosothiol derivative by nitrosation of the thiol group with NaNO₂under acidic conditions (pH is about 2.5) which yields the S-nitrosoderivative. Acids which can be used for this purpose include aqueoussulfuric, acetic and hydrochloric acids. The thiol precursor can also benitrosylated by reaction with an organic nitrite such as tert-butylnitrite, or a nitrosonium salt such as nitrosonium tetraflurorborate inan inert solvent.

Another group of NO adducts for use in the present invention, where theNO adduct is a compound that donates, transfers or releases nitricoxide, include compounds comprising at least one ON—O-, ON—N- orON—C-group. The compounds that include at least one ON—O-, ON-N- orON—C-group are preferably ON—O-, ON—N- or ON-C-polypeptides (the term“polypeptide” includes proteins and polyamino acids that do not possessan ascertained biological function, and derivatives thereof); ON—O,ON—N- or ON—C-amino acids (including natural and synthetic amino acidsand their stereoisomers and racemic mixtures); ON—O—, ON—N- orON—C-sugars; ON—O', ON—N- or ON—C-modified or unmodifiedoligonucleotides (comprising at least 5 nucleotides, preferably 5-200nucleotides); ON—O—, ON—N- or ON—C-straight or branched, saturated orunsaturated, aliphatic or aromatic, substituted or unsubstitutedhydrocarbons; and ON—O—, ON—N- or ON—C-heterocyclic compounds.

Another group of NO adducts for use in the present invention includenitrates that donate, transfer or release nitric oxide, such ascompounds comprising at least one O₂N—O—, O₂N—N—, O₂N—S- or O₂N—C—group. Preferred among these compounds are O₂N—O—, O₂N—N—, O₂N—S- orO₂N—C-polypeptides (the term “polypeptide” includes proteins and alsopolyamino acids that do not possess an ascertained biological function,and derivatives thereof); O₂N—O—, O₂N—N—, O₂N—S—, or O₂N—C-amino acids(including natural and synthetic amino acids and their stereoisomers andracemic mixtures); O₂N—O—, O₂N—N—, O₂N—S or O₂N—C-sugars; O₂N—O—,O₂N—N—, O₂N—S- or O₂N—C-modified and unmodified oligonucleotides(comprising at least 5 nucleotides, preferably 5-200 nucleotides);O₂N—O—, O₂N—N—, O₂N—S or O₂N—C-straight or branched, saturated orunsaturated, aliphatic or aromatic, substituted or unsubstitutedhydrocarbons; and O₂N—O—, O₂N—N—, O₂N—S— or O₂N—C-heterocycliccompounds. Preferred examples of compounds comprising at least oneO₂N—O—, O₂N—N—, O₂N—S- or O₂N—C— group include isosorbide dinitrate,isosorbide mononitrate, clonitrate, erythrityltetranitrate, mannitolhexanitrate, nitroglycerin, pentaerythritoltetranitrate, pentrinitroland propatylnitrate.

Another group of NO adducts are N-oxo-N-nitrosoamines that donate,transfer or release nitric oxide and are represented by the formula:R¹R²—N(O—M⁺)—NO, where R¹ and R² are each independently a polypeptide,an amino acid, a sugar, a modified or unmodified oligonucleotide, astraight or branched, saturated or unsaturated, aliphatic or aromatic,substituted or unsubstituted hydrocarbon, or a heterocyclic group, andM⁺ is as defined herein.

Another group of NO adducts are thionitrates that donate, transfer orrelease nitric oxide and are represented by the formula: R¹—(S)—NO₂,where R¹ is a polypeptide, an amino acid, a sugar, a modified orunmodified oligonucleotide, a straight or branched, saturated orunsaturated, aliphatic or aromatic, substituted or unsubstitutedhydrocarbon, or a heterocyclic group. Preferred are those compoundswhere R¹ is a polypeptide or hydrocarbon with a pair or pairs of thiolsthat are sufficiently structurally proximate, i.e., vicinal, that thepair of thiols will be reduced to a disulfide. Compounds which formdisulfide species release nitroxyl ion (NO−) and uncharged nitric oxide(NO.).

The present invention is also directed to compounds that stimulateendogenous NO or elevate levels of endogenous endothelium-derivedrelaxing factor (EDRF) in vivo or are substrates for the enzyme, nitricoxide synthase. Such compounds include, for example, L-arginine,L-homoarginine, and N-hydroxy-L-arginine, including their nitrosated andnitrosylated analogs (e.g., nitrosated L-arginine, nitrosylatedL-arginine, nitrosated N-hydroxy-L-arginine, nitrosylatedN-hydroxy-L-arginine, nitrosated L-homoarginine and nitrosylatedL-homoarginine), precursors of L-arginine and/or physiologicallyacceptable salts thereof, including, for example, citrulline, ornithine,glutamine, lysine, polypeptides comprising at least one of these aminoacids, inhibitors of the enzyme arginase (e.g., N-hydroxy-L-arginine and2(S)-amino-6-boronohexanoic acid) and the substrates for nitric oxidesynthase, cytokines, adenosin, bradykinin, calreticulin, bisacodyl, andphenolphthalein. EDRF is a vascular relaxing factor secreted by theendothelium, and has been identified as nitric oxide (NO) or a closelyrelated derivative thereof (Palmer et al, Nature, 327:524-526 (1987);Ignarro et al, Proc. Natl. Acad. Sci. USA, 84:9265-9269 (1987)).

The present invention is also based on the discovery that theadministration of a therapeutically effective amount of the compoundsand compositions described herein is effective for treating orpreventing sexual dysfunctions or enhancing sexual responses inpatients, including males and females. For example, the patient can beadministered a therapeutically effective amount of at least onenitrosated and/or nitrosylated potassium channel activator of thepresent invention. In another embodiment, the patient can beadministered a therapeutically effective amount of at least onepotassium channel activator, optionally substituted with at least one NOand/or NO₂ group, and at least one compound that donates, transfers orreleases nitric oxide as a charged species, or elevates levels ofendogenous EDRF or nitric oxide, or is a substrate for nitric oxidesynthase. In yet another embodiment, the patient can be administered atherapeutically effective amount of at least one potassium channelactivator, optionally substituted with at least one NO and/or NO₂ group,and at least one vasoactive agent, and, optionally, at least onecompound that donates, transfers or releases nitric oxide as a chargedspecies, or elevates levels of endogenous EDRF or nitric oxide, or is asubstrate for nitric oxide synthase. The compounds can be administeredseparately or in the form of a composition.

A vasoactive agent is any therapeutic agent capable of relaxing vascularsmooth muscle. Suitable vasoactive agents include, but are not limitedto, calcium blockers (such as, for example, nifedipine, veraparmil,diltiazem, gallopamil, niludipine, nimodipins, nicardipine, and thelike); β-blockers (such as, for example, butixamine,dichloroisoproterenol, propanolol, alprenolol, bunolol, nadolol,oxprenolol, perbutolol, pinodolol, sotalol, timolol, metoprolol,atenolol, acebutolol, bevantolol, pafenolol, tolamodol, and the like);long and short acting α-adrenergic receptor antagonist (such as, forexample, phenoxybenzamide, dibenamine, doxazosin, terazosin,phentolamine, tolazoline, prozosin, trimazosin, yohimbine, moxisylyteand the like); phosphodiesterase inhibitors (such as, for example,papaverine, zaprinast, sildenafil, IC 351 and the like); adenosine,ergot alkaloids (such as, for example, ergotamine, ergotamine analogs,including, for example, acetergamine, brazergoline, bromerguride,cianergoline, delorgotrile, disulergine, ergonovine maleate, ergotaminetartrate, etisulergine, lergotrile, lysergide, mesulergine, metergoline,metergotamine, nicergoline, pergolide, propisergide, proterguride,terguride and the like); vasoactive intestinal peptides (such as, forexample, peptide histidine isoleucine, peptide histidine methionine,substance P, calcitonin gene-related peptide, neurokinin A, bradykinin,neurokinin B. and the like); dopamine agonists (such as, for example,apomorphine, bromocriptine, testosterone, cocaine, strychnine, and thelike); opioid antagonists (such as, for example, naltrexone, and thelike); prostaglandins (such as, for example, alprostadil, prostaglandinE₂, prostaglandin F₂, misoprostol, enprostil, arbaprostil, unoprostone,trimoprostil, carboprost, limaprost, gemeprost, lantanoprost,ornoprostil, beraprost, sulpostrone, rioprostil, and the like);endothelin antagonists (such as, for example, bosentan, sulfonamideendothelin antagonists, BQ-123, SQ 28608, and the like); thromboxaneinhibitors (such as, for example, SQ 29548, BAY u3405, GR 32191, YM 158,and the like), and mixtures thereof.

Another embodiment of the present invention provides methods to preventor treat cardiovascular disorders, such as congestive heart failure andmyocardial ischemia, especially angina pectoris and arrhythmia;cerebrovascular disorders including those associated with cerebralischemia; hypertension; asthma; baldness; urinary incontinence;epilepsy; sleep disorders; gastrointestinal disorders; migraines;irritable bowel syndrome and sensitive skin, by administering to apatient in need thereof a therapeutically effective amount of thecompounds and/or compositions described herein. For example, the patientcan be administered a therapeutically effective amount of at least onenitrosated and/or nitrosylated potassium channel activator of thepresent invention. In another embodiment, the patient can beadministered a therapeutically effective amount of at least onepotassium channel activator, optionally substituted with at least one NOand/or NO₂ group, and at least one compound that donates, transfers orreleases nitric oxide as a charged species, or elevates levels ofendogenous EDRF or nitric oxide or is a substrate for nitric oxidesynthase. In yet another embodiment, the patient can be administered atherapeutically effective amount of at least one potassium channelactivator, optionally substituted with at least one NO and/or NO₂ group,and at least one vasoactive agent, and, optionally, at least onecompound that donates, transfers or releases nitric oxide as a chargedspecies, or elevates levels of endogenous EDRF or nitric oxide or is asubstrate for nitric oxide synthase. The potassium channel activatorsoptionally substituted with at least one NO and/or NO₂ group, nitricoxide donors and/or vasoactive agents can be administered separately orin the form of a composition. The compounds and compositions of thepresent invention can also be administered in combination with othermedications used for the treatment of these disorders.

When administered in vivo, the compounds and compositions of the presentinvention can be administered in combination with pharmaceuticallyacceptable carriers and in dosages described herein. When the compoundsand compositions of the present invention are administered as a mixtureof at least one nitrosated and/or nitrosylated potassium channelactivator or at least one potassium channel activator and at least onenitric oxide donor, they can also be used in combination with one ormore additional compounds which are known to be effective against thespecific disease state targeted for treatment (e.g., vasoactive agents).The nitric oxide donors and/or vasoactive agents can be administeredsimultaneously with, subsequently to, or prior to administration of thepotassium channel activators, including those that are substituted withone or more NO and/or NO₂ groups, and/or other additional compounds.

The compounds and compositions of the present invention can beadministered by any available and effective delivery system including,but not limited to, orally, bucally, parenterally, by inhalation spray(oral or nasal), by topical application, by injection into the corpuscavernosum tissue, by transurethral drug delivery, vaginally, orrectally (e.g., by the use of suppositories) in dosage unit formulationscontaining conventional nontoxic pharmaceutically acceptable carriers,adjuvants, and vehicles, as desired. Parenteral includes subcutaneousinjections, intravenous injections, intramuscular injections,intrasternal injections, and infusion techniques. Parenteral alsoincludes injection into the corpus cavernosum tissue, which can beconducted using any effective injection system including, but notlimited to, conventional syringe-and-needle systems or needlelessinjection devices.

Topical administration, which is well known to one skilled in the art,involves the delivery of pharmaceutical agents via percutaneous passageof the drug into the systemic circulation of the patient. Topicaladministration includes vaginal administration, vulval administration,penile administration and rectal administration. Topical administrationcan also involve transdermal patches or iontophoresis devices. Othercomponents can be incorporated into the transdermal patches as well. Forexample, compositions and/or transdermal patches can be formulated withone or more preservatives or bacteriostatic agents including, but notlimited to, methyl hydroxybenzoate, propyl hydroxybenzoate,chlorocresol, benzalkonium chloride, and the like.

Dosage forms for topical administration of the compounds andcompositions of the present invention preferably include creams, sprays,lotions, gels, ointments, emulsions, coatings for condoms, liposomes,foams, and the like. Administration of the cream, spray, lotion, gel,ointment, emulsion, coating, liposome, or foam can be accompanied by theuse of an applicator or by transurethral drug delivery using a syringewith or without a needle or penile insert or device, or by clitoral,vulval or vaginal delivery, and is within the skill of the art.Typically a lubricant and/or a local anesthetic for desensitization canalso be included in the formulation or provided for use as needed.Lubricants include, for example, K-Y jelly (available from Johnson &Johnson) or a lidocaine jelly, such as XYLOCAINE® 2% jelly (availablefrom Astra Pharmaceutical Products). Local anesthetics include, forexample, novocaine, procaine, tetracaine, benzocaine and the like.

Solid dosage forms for oral administration can include capsules,tablets, effervescent tablets, chewable tablets, pills, powders,effervescent powders, sachets, granules and gels. In such solid dosageforms, the active compounds can be admixed with at least one inertdiluent such as sucrose, lactose or starch. Such dosage forms can alsocomprise, as in normal practice, additional substances other than inertdiluents, e.g., lubricating agents such as magnesium stearate. In thecase of capsules, tablets, effervescent tablets, and pills, the dosageforms can also comprise buffering agents. Soft gelatin capsules can beprepared to contain a mixture of the active compounds or compositions ofthe present invention and vegetable oil.. Hard gelatin capsules cancontain granules of the active compound in combination with a solid,pulverulent carrier such as lactose, saccharose, sorbitol, mannitol,potato starch, corn starch, amylopectin, cellulose derivatives ofgelatin. Tablets and pills can be prepared with enteric coatings.

Liquid dosage forms for oral administration can include pharmaceuticallyacceptable emulsions, solutions, suspensions, syrups, and elixirscontaining inert diluents commonly used in the art, such as water. Suchcompositions can also comprise adjuvants, such as wetting agents,emulsifying and suspending agents, and sweetening, flavoring, andperfuming agents.

Suppositories for vaginal or rectal administration of the compounds andcompositions of the invention can be prepared by mixing the compounds orcompositions with a suitable nonirritating excipient such as cocoabutter and polyethylene glycols which are solid at room temperature butliquid at body temperature, such that they will melt and release thedrug.

Injectable preparations, for example, sterile injectable aqueous oroleaginous suspensions can be formulated according to the known artusing suitable dispersing agents, wetting agents and/or suspendingagents. The sterile injectable preparation can also be a sterileinjectable solution or suspension in a nontoxic parenterally acceptablediluent or solvent, for example, as a solution in 1,3-butanediol. Amongthe acceptable vehicles and solvents that can be used are water,Ringer's solution, and isotonic sodium chloride solution. Sterile fixedoils are also conventionally used as a solvent or suspending medium.

The compounds and compositions of the present invention will typicallybe administered in a pharmaceutical composition containing one or morecarriers or excipients, i.e., pharmaceutically acceptable organic orinorganic carrier substances suitable for parenteral application whichdo not deleteriously react with the active compounds. Examples ofpharmaceutically acceptable carriers include, for example, water, saltsolutions, alcohol, silicone, waxes, petroleum jelly, vegetable oils,polyethylene glycols, propylene glycol, liposomes, sugars, gelatin,lactose, amylose, magnesium stearate, talc, surfactants, silicic acid,viscous paraffin, perfume oil, fatty acid monoglycerides anddiglycerides, petroethral fatty acid esters, hydroxymethyl-cellulose,polyvinylpyrrolidone, and the like. The compositions can also includeone or more permeation enhancers including, for example,dimethylsulfoxide (DMSO), dimethyl formamide (DMF),N,N-dimethylacetamide (DMA), decylmethylsulfoxide (C10MSO), polyethyleneglycol monolaurate (PEGML), glyceral monolaurate, lecithin,1-substituted azacycloheptan-2-ones, particularly1-N-dodecylcyclazacylocoheptan-2-ones (available under the trademarkAzone™ from Nelson Research & Development Co., Irvine, Calif.), alcoholsand the like.

The pharmaceutical preparations can be sterilized and if desired, mixedwith auxiliary agents which do not deleteriously react with the activecompounds, e.g., lubricants, preservatives, stabilizers, wetting agents,emulsifiers, salts for influencing osmotic pressure, buffers, colorings,flavoring and/or aromatic substances, and the like. For parenteralapplication, particularly suitable vehicles consist of solutions,preferably oily or aqueous solutions, as well as suspensions, emulsions,or implants. Aqueous suspensions may contain substances which increasethe viscosity of the suspension and include, for example, sodiumcarboxymethyl cellulose, sorbitol and/or dextran. Optionally, thesuspension may also contain stabilizers.

The composition, if desired, can also contain minor amounts of wettingagents, emulsifying agents and/or pH buffering agents. The compositioncan be a liquid solution, suspension, emulsion, tablet, pill, capsule,sustained release formulation, or powder. The composition can beformulated as a suppository, with traditional binders and carriers suchas triglycerides. Oral formulations can include standard carriers suchas pharmaceutical grades of mannitol, lactose, starch, magnesiumstearate, sodium saccharine, cellulose, magnesium carbonate, and thelike.

Various delivery systems are known and can be used to administer thecompounds or compositions of the present invention, including, forexample, encapsulation in liposomes, microbubbles, emulsions,microparticles, microcapsules and the like. The required dosage can beadministered as a single unit or in a sustained release form.

The bioavailabilty of the compositions can be enhanced by micronizationof the formulations using conventional techniques such as grinding,milling, spray drying and the like in the presence of suitableexcipients or agents such as phospholipids or surfactants. Thebioavailability and absorption of the potassium channel activators canbe increased by the addition of tabletting excipients, such as, forexample β-cyclodextrin, a β-cyclodextrin derivative, such as forexample, hydroxypropyl-β-cyclodextrin (HPBCD), and the like.

The compounds and compositions of the present invention can beformulated as pharmaceutically acceptable salts. Pharmaceuticallyacceptable salts include, for example, alkali metal salts and additionsalts of free acids or free bases. The nature of the salt is notcritical, provided that it is pharmaceutically acceptable. Suitablepharmaceutically acceptable acid addition salts may be prepared from aninorganic acid or from an organic acid. Examples of such inorganic acidsinclude, but are not limited to, hydrochloric, hydrobromic, hydroiodic,nitric (nitrate salt), nitrous (nitrite salt), carbonic, sulfuric andphosphoric acid and the like. Appropriate organic acids include, but arenot limited to, aliphatic, cycloaliphatic, aromatic, heterocyclic,carboxylic and sulfonic classes of organic acids, such as, for example,formic, acetic, propionic, succinic, glycolic, gluconic, lactic, malic,tartaric, citric, ascorbic, glucuronic, maleic, fumaric, pyruvic,aspartic, glutamic, benzoic, anthranilic, mesylic, salicylic,p-hydroxybenzoic, phenylacetic, mandelic, embonic (pamoic),methanesulfonic, ethanesulfonic, benzenesulfonic, pantothenic,toluenesulfonic, 2-hydroxyethanesuifonic, sulfanilic, stearic, algenic,β-hydroxybutyric, cyclohexylaminosulfonic, galactaric and galacturonicacid and the like. Suitable pharmaceutically acceptable base additionsalts include, but are not limited to, metallic salts made fromaluminum, calcium, lithium, magnesium, potassium, sodium and zinc ororganic salts made from primary, secondary and tertiary amines, cyclicamines, N,N′-dibenzylethylenediamine, chloroprocaine, choline,diethanolamine, ethylenediamine, meglumine (N-methylglucamine) andprocaine and the like. All of these salts may be prepared byconventional means from the corresponding compound by reacting, forexample, the appropriate acid or base with the compound.

“Therapeutically effective amount” refers to the amount of the potassiumchannel activator, nitrosated and/or nitrosylated potassium channelactivator, nitric oxide donor and/or vasoactive agent that is effectiveto achieve its intended purpose. While individual patient needs mayvary, determination of optimal ranges for effective amounts of each ofthe compounds and compositions is within the skill of the art. Generallythe dosage regimen for treating a condition with the compounds and/orcompositions of this invention is selected in accordance with a varietyof factors, including the type, age, weight, sex, diet and medicalcondition of the patient, the severity of the dysfunction, the route ofadministration, pharmacological considerations such as the activity,efficacy, pharmacokinetic and toxicology profiles of the particularcompound used, whether a drug delivery system is used, and whether thecompound is administered as part of a drug combination and can beadjusted by one skilled in the art. Thus, the dosage regimen actuallyemployed may vary from the preferred dosage regimen set forth herein.

The amount of a given potassium channel activator (including nitrosatedand/or nitrosylated potassium channel activators) which will beeffective in the prevention or treatment of a particular dysfunction orcondition will depend on the nature of the dysfunction or condition, andcan be determined by standard clinical techniques, including referenceto Goodman and Gilman, supra; The Physician's Desk Reference, supra;Medical Economics Company, Inc., Oradell, N.J., 1995; and Drug Facts andComparisons, Inc., St. Louis, Mo., 1993. The precise dose to be used inthe formulation will also depend on the route of administration, and theseriousness of the dysfunction or disorder, and should be decided by thephysician and the patient's circumstances. Effective doses may beextrapolated from dose-response curves derived from in vitro or animalmodel test systems and are in the same ranges or less than as describedfor the commercially available compounds in the Physician's DeskReference, supra.

The usual doses of potassium channel activators (including nitrosatedand/or nitrosylated potassium channel activators) for intracavernosalinjection are about 0.001 mg/kg to about 30 mg/kg, and preferably about0.01 mg/kg to about 25 mg/kg. The oral dose of potassium channelactivators (including nitrosated and/or nitrosylated potassium channelactivators) are about 1 mg to about 100 mg preferably about 5 mg toabout 80 mg.

The doses of nitric oxide donors in the pharmaceutical composition canbe in amounts of about 0.001 mg to about 30 g and the actual amountadministered will be dependent on the specific nitric oxide donorcompound. For example, when L-arginine is the nitric oxide donor,L-arginine can be administered orally in an amount of about 0.25 gramsto about 10 grams (equivalent to about 0.5 grams to about 20 grams ofL-arginine glutamate), preferably about 2 grams to about 4 grams(equivalent to about 4 grams to about 8 grams of L-arginine glutamate);more preferably about 2.5 grams to about 3.5 grams (equivalent to about5 grams to about 7 grams of L-arginine glutamate); most preferably about3 grams (equivalent to 6 grams of L-arginine glutamate).

The nitrosated and/or nitrosylated potassium channel activators of theinvention are used at dose ranges and over a course of dose regimen andare administered in the same or substantially equivalentvehicles/carrier by the same or substantially equivalent as theirnon-nitrosated/nitrosylated counterparts. The nitrosated and/ornitrosylated compounds of the invention can also be used in lower dosesand in less extensive regimens of treatment. The amount of activeingredient that can be combined with the carrier materials to produce asingle dosage form will vary depending upon the host treated and theparticular mode of administration.

Particularly preferred methods of administration of the contemplatedpotassium channel activator compositions (including nitrosated and/ornitrosylated potassium channel activator compositions) for the treatmentof male sexual dysfunction are topical application, by injection intothe corpus cavernosum, by transurethral administration or by the use ofsuppositories. The preferred methods of administration for female sexualdysfunction are topical application or by the use of suppositories.

The present invention also provides pharmaceutical kits comprising oneor more containers filled with one or more of the ingredients of thepharmaceutical compounds and/or compositions of the present invention,including, one or more potassium channel activators, optionallysubstituted with one or more NO and/or NO₂ groups, and one or more ofthe NO donors, and one or more vasoactive agents described herein. Suchkits can also include, for example, other compounds and/or compositions(e.g., vasoactive agents, permeation enhancers, lubricants, and thelike), a device(s) for administering the compounds and/or compositions,and written instructions in a form prescribed by a governmental agencyregulating the manufacture, use or sale of pharmaceuticals or biologicalproducts, which instructions can also reflects approval by the agency ofmanufacture, use or sale for human administration.

EXAMPLE

The following non-limiting example is for purposes of illustration onlyand is not intended to limit the scope of the invention or claims.

Example 1 N-[2-methyl-2-(nitrosothio)propyl]-3-pyridylcarboxamide 1a.N-(2-methyl-2-sulfanylpropyl)-3-pyridylcarboxamide

1-Amino-2-methylpropane-2-thiol hydrochloride (1.10 g, 6.18 mmol) wasdissolved in DMF and nicotinoyl chloride hydrochloride (1.14 g, 8.03mmol) was slowly added as a solid. The mixture was cooled to 0° C. andtriethylamine (3.0 mL, 21.63 mmol) was slowly added. The mixture wasstirred for one half hour at 0° C., allowed to warm to room temperature,and stirred overnight. The reaction mixture was diluted with methylenechloride, washed with saturated sodium bicarbonate, brine, and driedover magnesium sulfate. The volatiles were removed under reducedpressure to give a pink oil. An excess of hydrogen chloride in ether wasadded to precipitate 831 mg. (55%) of the title compound, mp. 163-165°C. ¹H NMR (300 MHz, DMSO) δ9.00 (br s, 1H), 8.71 (dd, 1H, J=2.0, 4.9),8.20 (dt, 1H, J=2.0, 7.9), 7.51 (dd, 1H, J=4.9, 7.9), 3.44 (d, 2H,J=6.3), 1.32 (s, 6H).

1b. N-[2-methyl-2-(nitrosothio)propyl]-3-pyridylcarboxamide

The compound of Example 1a (73.5 mg, 0.298 mmol) was dissolved inmethanol and tert-butylnitrite (38.3 mg, 0.328 mmol) was added. Themixture was stirred for 45 minutes and the solvent removed under reducedpressure. An excess of hydrogen chloride in ether was added toprecipitate 45.2 mg (90%) of the title compound, mp. 125-127° C. ¹H NMR(300 MHz, DMSO) δ9.03 (br s, 1H), 8.73 (dd, 1, 2H, J=1.5, 4.8), 8.22 (brd, 1H, J=7.9), 7.53 (dd, 1H, J=4.8, 7.9) 3.47 (d, 2H, J=6.3), 1.34 (s,6H).

The disclosure of each patent, patent application and publication citedin the specification is hereby incorporated by reference herein in itsentirety.

Although the invention has been set forth in detail, one skilled in theart will appreciate that numerous changes and modifications can be madeto the invention without departing from the spirit and scope thereof.

What is claimed is:
 1. A compound of formula (I) or a pharmaceuticallyacceptable salt thereof: wherein the compound of formula (I) is:

wherein R₁ is:

wherein R₂ is a hydrogen atom or a halogen atom; B is oxygen or —N—CN;D₂ is Q or K; Q is —NO or —NO₂; K is—W_(a)—E_(b)—(C(R_(e))(R_(f)))_(p)—E_(c)—(C(R_(e))(R_(f)))_(x)—W_(d)—(C(R_(e))(R_(f)))_(y)—W_(i)—E_(j)—W_(g)—(C(R_(e))(R_(f)))_(z)—T—Q;a, b, c, d, g, i and j are each independently an integer from 0 to 3; p,x, y and z are each independently an integer from 0 to 10; W at eachoccurrence is independently —C(O)—, —C(S)—, —T—,—(C(R_(e))(R_(f)))_(h)—, an alkyl group, an aryl group, a heterocyclicring, an arylheterocyclic ring, or —(CH₂CH₂O)_(q)—; E at each occurrenceis independently —T—, an alkyl group, an aryl group,—(C(R_(e))(R_(f)))_(h)—, a heterocyclic ring, an arylheterocyclic ring,or —(CH₂CH₂O)_(q)—; h is an integer from 1 to 10; q is an integer from 1to 5; R_(e) and R_(f) are each independently a hydrogen, an alkyl, acycloalkoxy, a halogen, a hydroxy, an hydroxyalkyl, an alkoxyalkyl, anarylheterocyclic ring, an alkylaryl, a cycloalkylalkyl, aheterocyclicalkyl, an alkoxy, a haloalkoxy, an amino, an alkylamino, adialkylamino, an arylamino, a diarylamino, an alkylarylamino, analkoxyhaloalkyl, a haloalkoxy, a sulfonic acid, a sulfonic ester, analkylsulfonic acid, an arylsulfonic acid, an arylalkoxy, an alkylthio,an arylthio, a cycloalkylthio, a cycloalkenyl, a cyano, an aminoalkyl,an aminoaryl, an aryl, an arylalkyl, an alkylaryl, a carboxamido, analkylcarboxamido, an arylcarboxamido, an amidyl, a carboxyl, acarbamoyl, an alkylcarboxylic acid, an arylcarboxylic acid, analkylcarbonyl, an arylcarbonyl, an ester, a carboxylic ester, analkylcarboxylic ester, an arylcarboxylic ester, a haloalkoxy, asulfonamido, an alkylsulfonamido, an arylsulfonamido, a sulfonic ester,a urea, a phosphoryl, a nitro, —T—Q , or (C(R_(e))(R_(f)))_(k)—T—Q, orR_(e) and R_(f) taken together with the carbons to which they areattached form a carbonyl, a methanthial, a heterocyclic ring, acycloalkyl group or a bridged cycloalkyl group; k is an integer from 1to 3; T at each occurrence is independently a covalent bond, a carbonyl,an oxygen, —S(O)_(o)- or —N(R_(a))R_(i)—; o is an integer from 0 to 2;R_(a) is a lone pair of electrons, a hydrogen or an alkyl group; R_(i)is a hydrogen, an alkyl, an aryl, an alkylcarboxylic acid, anarylcarboxylic acid, an alkylcarboxylic ester, an arylcarboxylic ester,an alkylcarboxamido, an arylcarboxamido, an alkylaryl, an alkylsulfinyl,an alkylsulfonyl, an arylsulfinyl, an arylsulfonyl, a sulfonamido, acarboxamido, a carboxylic ester, an amino alkyl, an amino aryl,—CH₂—C(T—Q)(R_(e))(R_(f)), or —(N₂O₂—)⁻.M⁺, wherein M⁺ is an organic orinorganic cation; with the proviso that when R_(i) is—CH₂—C(T—Q)(R_(e))(R_(f)) or —(N₂O₂)⁻.M⁺, or R_(e) or R_(f) are T—Q or(C(R_(e))(R_(f)))_(k)—T—Q, then the “—T—Q” subgroup can be a hydrogen,an alkyl, an alkoxy, an alkoxyalkyl, an aminoalkyl, a hydroxy, aheterocyclic ring or an aryl group; with the proviso that when the T in“—T—Q” is oxygen then Q is not —NO₂; and provided that the compoundcontains at least one nitrite, nitrate, thionitrite or thionitrategroup; provided that the “—T—D₂” group is not N′-(2-nitroxyethyl),N′-(3-nitroxy-propyl), N′-(4-nitrobenzyl),N′-(2-(4-nitrophenyl)-2-nitroxyethyl), N′-(2-methyl-2-nitroxyethyl),N′-(2,3-dinitroxypropyl), N,N′-bis-(2-nitroxyethyl) orN′-(1-methyl-2-(4-nitrophenyl)-2-nitroxyethyl).
 2. The compound of claim1, wherein the compound of Formula (I) is a nitrosylated nicorandil or anitrosated and nitrosylated nicorandil.
 3. A composition comprising thecompound of claim 1 and a pharmaceutically acceptable carrier.
 4. Amethod for treating a sexual dysfunction in a patient in need thereofcomprising administering to the patient a therapeutically effectiveamount of the composition of claim
 3. 5. The method of claim 4, whereinthe patient is female.
 6. The method of claim 4, wherein the patient ismale.
 7. The method of claim 4, wherein the composition is administeredby intracavernosal injection, by transurethral application or topically.8. The method of claim 7, wherein the composition is administeredtopically in the form of a cream, a spray, a lotion, a gel, an ointment,an emulsion, a foam, a coating for a condom, or a liposome composition.9. A method for treating a cardiovascular disorder, a cerebrovasculardisorder, hypertension or asthma in a patient in need thereof comprisingadministering to the patient a therapeutically effective amount of thecomposition of claim
 3. 10. The composition of claim 3, furthercomprising at least one vasoactive agent.
 11. The composition of claim10, wherein the vasoactive agent is a calcium channel blocker, anα-adrenergic receptor antagonist, a β-blocker, a phosphodiesteraseinhibitor, adenosine, an ergot alkaloid, a vasoactive intestinalpeptide, a prostaglandin, a dopamine agonist, an opioid antagonist, anendothelin antagonist, a thromboxane inhibitor or a mixture thereof. 12.A method for treating a sexual dysfunction in a patient in need thereofcomprising administering to the patient a therapeutically effectiveamount of the composition of claim
 10. 13. The method of claim 12,wherein the patient is female.
 14. The method of claim 12, wherein thepatient is male.
 15. The method of claim 12, wherein the composition isadministered by intracavernosal injection, by transurethral applicationor topically.
 16. The method of claim 15, wherein the composition isadministered topically in the form of a cream, a spray, a lotion, a gel,an ointment, an emulsion, a foam, a coating for a condom, or a liposomecomposition.
 17. A method for treating a cardiovascular disorder, acerebrovascular disorder, hypertension or asthma in a patient in needthereof comprising administering to the patient a therapeuticallyeffective amount of the composition of claim
 10. 18. A compositioncomprising at least one compound of claim 1 and at least one compoundthat donates, transfers, or releases nitric oxide, induces theproduction of endogenous nitric oxide or endothelium-derived relaxingfactor, stimulates endogenous synthesis of nitrogen monoxide or is asubstrate for nitric oxide synthase or a pharmaceutically acceptablesalt thereof.
 19. The composition of claim 18, wherein the at least onecompound that donates, transfers, or releases nitric oxide, induces theproduction of endogenous nitric oxide or endothelium-derived relaxingfactor, stimulates endogenous synthesis of nitrogen monoxide or is asubstrate for nitric oxide synthase is an S-nitrosothiol.
 20. Thecomposition of claim 19, wherein the S-nitrosothiol isS-nitroso-N-acetylcysteine, S-nitroso-captopril,S-nitroso-N-acetylpenicillamine, S-nitroso-homocysteine,S-nitroso-cysteine or S-nitroso-glutathione.
 21. The composition ofclaim 19, wherein the S-nitrosothiol is: (i) HS(C(R_(e))(R_(f)))_(m)SNO;(ii) ONS(C(R_(e))(R_(f)))_(m)R_(e); and (iii)H₂N—CH(CO₂H)—(CH₂)_(m)—C(O)NH—CH(CH₂SNO)—C(O)NH—CH₂—CO₂H; wherein m isan integer from 2 to 20; R_(e) and R_(f) are each independently ahydrogen, an alkyl, a cycloalkoxy, a halogen, a hydroxy, anhydroxyalkyl, an alkoxyalkyl, an arylheterocyclic ring, an alkylaryl, acycloalkylalkyl, a heterocyclicalkyl, an alkoxy, a haloalkoxy, an amino,an alkylamino, a dialkylamino, an arylamino, a diarylamino, analkylarylamino, an alkoxyhaloalkyl, a haloalkoxy, a sulfonic acid, asulfonic ester, an alkylsulfonic acid, an arylsulfonic acid, anarylalkoxy, an alkylthio, an arylthio, a cycloalkylthio, a cycloalkenyl,a cyano, an aminoalkyl, an aminoaryl, an aryl, an arylalkyl, analkylaryl, a carboxamido, an alkylcarboxamido, an arylcarboxamido, anamidyl, a carboxyl, a carbamoyl, a carbamate, an alkylcarboxylic acid,an arylcarboxylic acid, an alkylcarbonyl, an arylcarbonyl, an ester, acarboxylic ester, an alkylcarboxylic ester, an arylcarboxylic ester, ahaloalkoxy, a sulfonamido, an alkylsulfonamido, an arylsulfonamido, asulfonic ester, a urea, a phosphoryl, a nitro, —T—Q , or(C(R_(e))(R_(f)))_(k)—T—Q, or R_(e) and R_(f) taken together with thecarbons to which they are attached form a carbonyl, a methanthial, aheterocyclic ring, a cycloalkyl group or a bridged cycloalkyl group; Qis —NO or —NO₂; and T is independently a covalent bond, a carbonyl, anoxygen, —S(O)_(o)- or —N(R_(a))R_(i)—, wherein o is an integer from 0 to2, R_(a) is a lone pair of electrons, a hydrogen or an alkyl group;R_(i) is a hydrogen, an alkyl, an aryl, an alkylcarboxylic acid, an arylcarboxylic acid, an alkylcarboxylic ester, an arylcarboxylic ester, analkylcarboxamido, an arylcarboxamido, an alkylaryl, an alkylsulfinyl, analkylsulfonyl, an arylsulfinyl, an arylsulfonyl, a sulfonamido, acarboxamido, a carboxylic ester, an amino alkyl, an amino aryl,—CH₂—C(T—Q)(R_(e))(R_(f)), or —(N₂O₂—).M⁺, wherein M⁺ is an organic orinorganic cation; with the proviso that when R_(i) is—CH₂—C(T—Q)(R_(e))(R_(f)) or —(N₂O₂—).M⁺; then “—T—Q” can be a hydrogen,an alkyl group, an alkoxyalkyl group, an aminoalkyl group, a hydroxygroup pan aryl group.
 22. The composition of claim 18, wherein the atleast one compound that donates, transfers, or releases nitric oxide,induces the production of endogenous nitric oxide or endothelium-derivedrelaxing factor, stimulates endogenous synthesis of nitrogen monoxide oris a substrate for nitric oxide synthase is: (i) a compound thatcomprises at least one ON—O—, ON—N- or ON—C— group; (ii) a compound thatcomprises at least one O₂N—O—, O₂N—N—, O₂N—S- or —O₂N—C— group; (iii) aN-oxo-N-nitrosoamine having the formula: R¹R²—N(O—M⁺)—NO, wherein R¹ andR² are each independently a polypeptide, an amino acid, a sugar, anoligonucleotide, a straight or branched, saturated or unsaturated,aliphatic or aromatic, substituted or unsubstituted hydrocarbon, or aheterocyclic group, and M⁺ is an organic or inorganic cation.
 23. Thecomposition of claim 22, wherein the compound comprising at least oneON—O—, ON—N- or ON—C— group is an ON—O-polypeptide, an ON—N-polypeptide,an ON—C-polypeptide, an ON—O-amino acid, an ON—N-amino acid, anON—C-amino acid, an ON—O-sugar, an ON—N-sugar, an ON—C-sugar, anON—O-oligonucleotide, an ON—N-oligonucleotide, an ON—C-oligonucleotide,a straight or branched, saturated or unsaturated, substituted orunsubstituted, aliphatic or aromatic ON—O-hydrocarbon, a straight orbranched, saturated or unsaturated, substituted or unsubstituted,aliphatic or aromatic ON—N-hydrocarbon, a straight or branched,saturated or unsaturated, substituted or unsubstituted, aliphatic oraromatic ON—C-hydrocarbon, an ON—O-heterocyclic compound, anON—N-heterocyclic compound or a ON—C-heterocyclic compound.
 24. Thecomposition of claim 22, wherein compound comprising at least oneO₂N—O—, O₂N—N—, O₂N—S- or O₂N—C— group is an O₂N—O-polypeptide, anO₂N—N-polypeptide, an O₂N—S-polypeptide, an O₂N—C-polypeptide, anO₂N—O-amino acid, O₂N—N-amino acid, O₂N—S-amino acid, an O₂N—C-aminoacid, an O₂N—O-sugar, an O₂N—N-sugar, O₂N—S-sugar, an O₂N—C-sugar, anO₂N—O-oligonucleotide, an O₂N—N-oligonucleotide, anO₂N—S-oligonucleotide, an O₂N—C-oligonucleotide, a straight or branched,saturated or unsaturated, aliphatic or aromatic, substituted orunsubstituted O₂N—O-hydrocarbon, a straight or branched, saturated orunsaturated, aliphatic or aromatic, substituted or unsubstitutedO₂N—N-hydrocarbon, a straight or branched, saturated or unsaturated,aliphatic or aromatic, substituted or unsubstituted O₂N—S-hydrocarbon, astraight or branched, saturated or unsaturated, aliphatic or aromatic,substituted or unsubstituted O₂N—C-hydrocarbon, an O₂N—O-heterocycliccompound, an O₂N—N-heterocyclic compound, an O₂N—S-heterocyclic compoundor an O₂N—C-heterocyclic compound.
 25. The composition of claim 18,wherein the at least one compound that donates, transfers, or releasesnitric oxide, induces the production of endogenous nitric oxide orendothelium-derived relaxing factor, stimulates endogenous synthesis ofnitrogen monoxide or is a substrate for nitric oxide synthase, isL-arginine, L-homoarginine, N-hydroxy-L-arginine, nitrosated L-arginine,nitrosylated L-arginine, nitrosated N-hydroxy-L-arginine, nitrosylatedN-hydroxy-L-arginine, citrulline, ornithine, glutamine, lysine,polypeptides comprising at least one of these amino acids or inhibitorsof the enzyme arginase.
 26. A method for treating a sexual dysfunctionin a patient in need thereof comprising administering to the patient atherapeutically effective amount of the composition of claim
 18. 27. Themethod of claim 26, wherein the patient is female.
 28. The method ofclaim 26, wherein the patient is male.
 29. The method of claim 26,wherein the composition is administered by intracavernosal injection, bytransurethral application or topically.
 30. The method of claim 29,wherein the composition is administered topically in the form of acream, a spray, a lotion, a gel, an ointment, an emulsion, a foam, acoating for a condom, or a liposome composition.
 31. A method fortreating a cardiovascular disorder, a cerebrovascular disorder,hypertension or asthma in a patient in need thereof comprisingadministering to the patient a therapeutically effective amount of thecomposition of claim
 18. 32. The composition of claim 18, furthercomprising at least one vasoactive agent.
 33. The composition of claim32, wherein the vasoactive agent is a calcium channel blocker, anα-adrenergic receptor antagonist, a β-blocker, a phosphodiesteraseinhibitor, adenosine, an ergot alkaloid, a vasoactive intestinalpeptide, a prostaglandin, a dopamine agonist, a prostaglandin, an opioidantagonist, an endothelin antagonist, a thromboxane inhibitor or amixture thereof.
 34. A method for treating a sexual dysfunction in apatient in need thereof comprising administering to the patient atherapeutically effective amount of the composition of claim
 32. 35. Themethod of claim 34, wherein the patient is female.
 36. The method ofclaim 34, wherein the patient is male.
 37. The method of claim 34,wherein the composition is administered by intracavernosal injection, bytransurethral application or topically.
 38. The method of claim 37,wherein the composition is administered topically in the form of acream, a spray, a lotion, a gel, an ointment, an emulsion, a foam, acoating for a condom, or a liposome composition.
 39. A method fortreating a cardiovascular disorder, a cerebrovascular disorder,hypertension or asthma in a patient in need thereof comprisingadministering to the patient a therapeutically effective amount of thecomposition of claim
 32. 40. A kit comprising at least one compound ofclaim 1 and at least one compound that donates, transfers, or releasesnitric oxide, induces the production of endogenous nitric oxide orendothelium-derived relaxing factor, stimulates endogenous synthesis ofnitrogen monoxide or is a substrate for nitric oxide synthase, or apharmaceutically acceptable salt thereof.
 41. The kit of claim 40,further comprising at least one vasoactive agent.
 42. The kit of claim40, wherein the compound of claim 2 and the compound that donates,transfers, or releases nitric oxide, induces the production ofendogenous nitric oxide or endothelium-derived relaxing factor,stimulates endogenous synthesis of nitrogen monoxide or is a substratefor nitric oxide synthase, are separate components in the kit.
 43. Thekit of claim 40, wherein the compound of claim 2 and the compound thatdonates, transfers, or releases nitric oxide, induces the production ofendogenous nitric oxide or endothelium-derived relaxing factor,stimulates endogenous synthesis of nitrogen monoxide or is a substratefor nitric oxide synthase are in the form of a composition in the kit.